The Eucharist in Christian History: A Comparative Theological Study

Introduction

The Eucharist (also called the Lord’s Supper or Holy Communion) has been the central sacrament of Christianity since the time of Jesus, who at the Last Supper told his disciples, “This is my body… this is my blood… do this in remembrance of me” (Luke 22:19-20; cf. 1 Cor 11:23-25). Christians universally agree that the Eucharist is a sacred meal commemorating Christ’s sacrifice, but they have diverged historically on how Christ is present in the bread and wine and what the rite accomplishes. Two major theological perspectives crystallized in the Reformation era and remain influential today: the Catholic Church’s doctrine (which holds that upon consecration the bread and wine become the body and blood of Christ, a change termed transubstantiation, and that the Eucharist is also a sacrificial re-presentation of Christ’s offering) and the view of John Calvin and the Reformed tradition (which holds that Christ is truly spiritually present and received in the Supper, but the bread and wine remain unchanged – the sacrament is a means of grace by faith, not a literal sacrifice or physical transformation).

This study surveys the development of Eucharistic theology through four historical periods, using primary sources to trace how Christian understanding of the Lord’s Supper evolved and how each era’s dominant views relate to the later Catholic and Calvinist positions. The periods considered are: (1) the Early Church (up to ~150 AD), (2) 150 AD to the Council of Nicaea (325 AD), (3) Post-Nicaea to the Reformation (325–1500s), and (4) the Reformation to Modern Times. In each, we will examine key writings (Church Fathers, councils, scholastics, Reformers, etc.), noting doctrinal shifts and debates. Throughout, a comparative lens will be applied – highlighting where Catholic theology finds support or development, and where Calvin’s later perspective converges or contrasts – including analysis of underlying assumptions (such as scriptural authority vs. church tradition). The goal is an objective, scholarly overview accessible to theologians and clergy, illuminating the complexities of Eucharistic doctrine in history and the justification each side finds (or doesn’t find) for its views. All claims are documented with primary sources or modern scholarly assessments for accuracy.

Early Church (Pre-150 AD)

In the first generations of the Church, the Eucharist was celebrated as a sacred rite of fellowship with Christ. Although detailed theological explanations were few, surviving sources show that early Christians held a realist view of the Eucharist – they treated the bread and wine as in some sense truly the body and blood of Christ – while also seeing the ritual as a thanksgiving (eucharistia) and memorial. Notably, no evidence suggests a merely symbolic or metaphorical understanding among orthodox Christians in this period. Modern patristic scholars affirm this: “Eucharistic teaching… was in general unquestioningly realist, i.e., the consecrated bread and wine were taken to be… the Saviour’s body and blood”, observes J. N. D. Kelly (What the Early Church Believed: The Real Presence | Catholic Answers Tract). This does not mean the theology was fully developed, but the basic assumption of Christ’s real presence was already in place.

New Testament foundations influenced early belief. Saint Paul’s first letter to the Corinthians (c. 54 AD) speaks of the bread as a “participation in the body of Christ” and warns that those who eat and drink unworthily are “guilty of the body and blood of the Lord” (1 Cor 10:16, 11:27). Such language strongly implies that the Eucharist was not seen as an empty symbol – one would not be “guilty” of Christ’s body and blood by misusing mere bread and wine. Early Christians took these apostolic teachings to heart. The Didache (a Syrian Christian text often dated to ~90–100 AD) provides one of the earliest glimpses of Eucharistic practice. It presents prayers over the cup and bread that thank God for “the holy vine of David” and “the life and knowledge” revealed through Jesus, and then says: “As this broken bread was scattered upon the mountains and gathered into one, so let Your Church be gathered together from the ends of the earth…” (Didache 9.4). While the Didache’s language emphasizes thanksgiving and unity, it also calls the meal “sacrifice” in a spiritual sense (Didache 14) and restricts participation to the baptized, indicating the rite’s sanctity. This reflects an early understanding of the Eucharist as both a thanksgiving memorial and a holy communion in Christ’s body (even if the Didache does not explicitly use the phrase “body and blood of Christ”).

By the early 2nd century, Church Fathers clearly affirm the Real Presence. Ignatius of Antioch (d. c.107), a bishop and martyr who learned the faith within living memory of the apostles, is unambiguous. He chastises a heretical group for abstaining from the Eucharist “because they do not confess the Eucharist to be the flesh of our Savior Jesus Christ” (CHURCH FATHERS: Epistle to the Smyrnaeans (St. Ignatius)). In his letter To the Smyrnaeans, Ignatius writes: “They abstain from the Eucharist and from prayer, because they confess not the Eucharist to be the flesh of our Saviour Jesus Christ, which suffered for our sins, and which the Father, of His goodness, raised up again” (CHURCH FATHERS: Epistle to the Smyrnaeans (St. Ignatius)). Here “the Eucharist” is explicitly identified with Christ’s flesh. Ignatius also spoke of “the bread of God… which is the flesh of Jesus Christ” and “the drink of God… which is His blood” (Views on the Eucharist - 110 AD | TexAgs). Such statements show that, for Ignatius, the Eucharist was no mere symbol but mysteriously identical with Jesus’ incarnate flesh and blood – a direct affirmation of real presence. It is telling that Ignatius uses this doctrine as a litmus test of true belief in Christ’s real incarnation (the Docetist heretics denied Christ had real human flesh, so they refused to acknowledge the Eucharist as His flesh). In other words, early Christians linked the Eucharist tightly to core Christology.

Other writings from this period reinforce this view. Pliny the Younger (c. 112 AD), a Roman official, noted in a letter that Christians “meet before dawn and sing hymns to Christ… and partake of a meal – food of an ordinary and innocent kind.” While Pliny did not grasp its significance, Christians understood that “ordinary food” to be no longer ordinary in meaning. Around the same time, Saint Justin Martyr (c. 150 AD) provides one of the earliest detailed descriptions of the Eucharistic celebration and its theology. In his First Apology addressed to the Roman emperor, Justin explains the Christian liturgy of “the bread and wine mixed with water”, stating: “This food is called among us Εὐχαριστία [Eucharist]… not as common bread and common drink do we receive these; but in like manner as Jesus Christ our Savior, having been made flesh by the Word of God, had both flesh and blood for our salvation, so likewise have we been taught that the food which is blessed by the prayer of His word… is the flesh and blood of that Jesus who was made flesh.” (CHURCH FATHERS: The First Apology (St. Justin Martyr)). This remarkable passage shows Justin paralleling the Incarnation (“Word made flesh”) with the Eucharist (bread becoming flesh): the Eucharistic bread and cup are distinct from normal food, and Christians are “taught” to regard them as truly Christ’s flesh and blood, given for our salvation. Justin even anticipates the later question of how the bread and wine relate to Christ’s body: he notes that the elements nourish our bodies by digestion (“our flesh and blood are nourished by transformation of the food”) (CHURCH FATHERS: The First Apology (St. Justin Martyr)), implying the appearances of bread remain as food, yet in a mystery the sustenance they provide is no longer ordinary but a participation in Christ. While Justin does not use Aristotelian terms, he clearly espouses a real identification: the Eucharist is Christ’s body and blood, instituted by Jesus’ own words at the Last Supper (CHURCH FATHERS: The First Apology (St. Justin Martyr)). It is also significant that Justin roots this belief in apostolic tradition – “the apostles, in the memoirs composed by them (the Gospels), have delivered unto us that Jesus took bread and said, ‘This is My body…’” (CHURCH FATHERS: The First Apology (St. Justin Martyr)) – demonstrating that early Christians justified their Eucharistic realism by Scripture (the words of institution) as well as the teaching handed down in the Church. There was as yet no notion that one must find an alternative, purely symbolic interpretation of Christ’s words; they took them at face value.

To summarize the consensus of the pre-150 Church: the Eucharist was held in extremely high regard, considered in some real way to be the body and blood of Christ, and was guarded from profanation. Those like Ignatius and Justin who comment on it do so in a realist fashion – “the flesh of Jesus,” “not common bread,” “becomes the flesh and blood of Christ,” etc. There is no record of internal controversy on whether Christ is truly present; the controversies were with outsiders or heretics (e.g. Gnostics/Docetists) who denied either the Eucharist’s sanctity or Christ’s real humanity. The theology, however, was in a primitive, non-technical form. The exact manner of Christ’s presence was not spelled out beyond calling it a mystery based on Christ’s words and power. Sacrificial terminology appears (e.g. calling the Eucharist the Christian “sacrifice” of praise or first-fruits ( Philip Schaff: ANF01. The Apostolic Fathers with Justin Martyr and Irenaeus - Christian Classics Ethereal Library ) ( Philip Schaff: ANF01. The Apostolic Fathers with Justin Martyr and Irenaeus - Christian Classics Ethereal Library )), which later becomes important in Catholic theology, but in this era it simply meant that the Eucharist was offered to God in thanksgiving. Importantly, the authority structure for doctrine was not “Scripture alone” (sola Scriptura) but Scripture as understood in the living community. The earliest Christian writers appeal to the teachings of the apostles and the practice of the Church as justification for what they believe about the Eucharist. For example, Justin says “we have been taught” this doctrine – taught by whom? By the Church’s apostolic tradition. And Ignatius insists on unity with the bishop in celebrating the Eucharist, implying an authoritative structure to safeguard the rite (CHURCH FATHERS: Epistle to the Smyrnaeans (St. Ignatius)) (CHURCH FATHERS: Epistle to the Smyrnaeans (St. Ignatius)). This aligns more with the later Catholic view that Sacred Tradition and church authority guide doctrine. Calvin and the Reformers, who would emphasize a return to Scripture’s text, generally acknowledged the early church’s faith in Christ’s real presence, although they argued the early Fathers did not define metaphysical mechanisms and often spoke of “figures” and “symbols” alongside realism. Indeed, even in this early period we see a sacramental mentality: the bread and wine are earthly elements that signify a divine reality. But crucially, the sign is not empty – it effectually contains or conveys the reality it signifies. This is the seed of what would later flower into the full-fledged sacramental doctrines of both East and West.

In summary, the ante-Nicene (pre-325) Church up to 150 AD provides a foundation that strongly supports the Catholic notion of the Real Presence, and indeed Catholics cite these early witnesses frequently as proof that their doctrine is original. Calvinists likewise respect these sources; Calvin himself quoted Ignatius and others, agreeing that Christ is truly given in the Eucharist. Where they differ is in interpretation: a Catholic reading Ignatius (“the Eucharist is the flesh of Christ”) takes it as straightforward affirmation of the objective change in the elements, while a Reformed reading might allow that language to be a devotional way of saying Christ’s life or power is present through the Eucharist, without requiring the bread to cease being bread. At this stage, however, such nuances were not debated – the Church was “one” in Eucharistic faith, professing in worship what one later martyr, Saint Polycarp (c. 155), simply called “the cup of salvation and the bread of eternal life”. The groundwork was laid for later theological articulation.

150 AD to Nicaea (325 AD)

By the late 2nd and 3rd centuries, reflections on the Eucharist grew more detailed as theologians confronted new challenges and used Greek philosophical concepts to explain Christian doctrine. This period – from the Apologists and Irenaeus (c. 150–200) through the pre-Nicene Fathers (3rd century) – shows a continuity in affirming the Eucharist as truly Christ’s body and blood, along with emerging ideas about how the earthly elements relate to the heavenly reality. There is also an increased emphasis on the Eucharist as a sacrifice or offering, and on its mystical efficacy (e.g. bringing unity, immortality). These developments provide important background for later doctrinal definitions. We will examine key figures: Irenaeus of Lyons, Tertullian, Origen, Cyprian, and others, and how their teaching relates to what would become the Catholic and Reformed positions.

Saint Irenaeus (c. 130–c. 202), bishop of Lyons, was a disciple of Polycarp and thus a spiritual grandson of the apostle John. Writing around 180 AD against the Gnostic heretics, Irenaeus invokes Eucharistic doctrine as proof of the high value of creation and the reality of Christ’s incarnation. In Against Heresies, he asks how the Gnostics can deny the resurrection of the flesh when Christ has given us his flesh to eat: “How can they say that the flesh, which is nourished with the body of the Lord and with His blood, goes to corruption and does not partake of life? … For as the bread, which is produced from the earth, when it receives the invocation of God, is no longer common bread, but the Eucharist, consisting of two realities, earthly and heavenly; so also our bodies, when they receive the Eucharist, are no longer corruptible, having the hope of the resurrection.” (ＩＲＥＮＡＥＵＳ：　”Ｎｏ　Ｌｏｎｇｅｒ　Ｃｏｍｍｏｎ　Ｂｒｅａｄ” – Ｐｈｉｌｉｐ　Ｄｅｒｒｉｄａ) (ＩＲＥＮＡＥＵＳ：　”Ｎｏ　Ｌｏｎｇｅｒ　Ｃｏｍｍｏｎ　Ｂｒｅａｄ” – Ｐｈｉｌｉｐ　Ｄｅｒｒｉｄａ). Several points in this rich passage deserve emphasis: (1) Irenaeus calls the consecrated bread “no longer common bread” but Eucharist – a term signifying it has been set apart and transformed in status. It now consists of “two realities, earthly and heavenly.” In other words, after the prayer of consecration, the bread remains in its natural earthly reality (it still appears as bread), but it now also contains a heavenly reality – Christ’s Body. This is an early attempt to articulate how the bread is Christ’s body: it is both earthly and heavenly. This formulation, interestingly, resonates with what later theologians like Luther or the Eastern Orthodox would say (that the bread becomes a bearer of Christ while remaining bread), whereas the later Catholic doctrine of transubstantiation would use a different philosophical framework (earthly “accidents” remain, but the underlying substance becomes heavenly). What is clear is that Irenaeus affirms a transformation: “no longer common bread” implies a real change by divine action. (2) Irenaeus ties the Eucharist to salvation of the flesh – “our bodies, nourished by Christ’s body and blood, have the hope of resurrection”. This underscores the sacramental efficacy of the Eucharist: it is a channel of divine life, conferring immortality (an idea that will recur in later Fathers). (3) His argument presupposes that all orthodox Christians of his time share this belief about the Eucharist; he introduces it “incidentally” while refuting heretics (What the Early Church Believed: The Real Presence | Catholic Answers Tract), indicating it was uncontroversial among the faithful. Irenaeus also explicitly says “the bread which is of the earth, receiving the invocation of God, is no longer common bread but the Eucharist… the body of Christ” (ＩＲＥＮＡＥＵＳ：　”Ｎｏ　Ｌｏｎｇｅｒ　Ｃｏｍｍｏｎ　Ｂｒｅａｄ” – Ｐｈｉｌｉｐ　Ｄｅｒｒｉｄａ) and “the cup… he has declared to be His own blood”. In another fragment, he writes: “He took from among creation that which is bread…and gave thanks, saying ‘This is My body.’ The cup likewise, which is from among the creation… He confessed to be His blood” – thus, “He taught the new sacrifice of the New Covenant” (What the Early Church Believed: The Real Presence | Catholic Answers Tract). This shows Irenaeus understood the Last Supper words literally and saw the Eucharist as the fulfillment of Malachi’s prophecy of a pure offering among the nations.

St. Irenaeus’ theology is very congenial to the later Catholic position: he affirms real presence unambiguously and even speaks of the Eucharist as sacrifice and first-fruits offered to God (Against Heresies IV.17-18) ( Philip Schaff: ANF01. The Apostolic Fathers with Justin Martyr and Irenaeus - Christian Classics Ethereal Library ) ( Philip Schaff: ANF01. The Apostolic Fathers with Justin Martyr and Irenaeus - Christian Classics Ethereal Library ). The Catholic Church often cites Irenaeus for his line that the Eucharist consists of “an earthly and a heavenly reality” as an early witness to a mysterious change in the elements. Calvin and Reformed theologians likewise claim Irenaeus’ support to an extent – noting that he did not teach a crassly material view but a spiritual reality united to the material bread. In fact, Irenaeus stops short of saying the bread’s substance ceases to exist; rather, he says it becomes a vehicle of Christ’s presence and a pledge of resurrection. A Reformed reading might say this is compatible with believing in a spiritual presence united with the visible elements (which is essentially Calvin’s view), whereas a Roman Catholic reading would emphasize that Irenaeus clearly did not consider the Eucharistic bread ordinary food any longer, but truly Christ’s body – a difference more of philosophical explanation than of experiential belief.

Contemporaries and successors of Irenaeus expressed similar realism. Tertullian (c. 155–240), a theologian from North Africa (and the first Father to write in Latin), frequently spoke of the Eucharist as the body and blood of the Lord. In doing so, he also introduced the term “figure” to describe the elements. In one apologetic work against a gnostic-like argument, Tertullian writes of Christ at the Last Supper: “Having taken the bread and given it to His disciples, He made it His own body by saying, ‘This is My body,’ that is, the figure of My body” (Real presence of Christ in the Eucharist - Wikipedia). This statement – “the figure of My body” – has sparked much debate. At face value, Tertullian seems to interpret “this is My body” to mean “this represents My body.” Indeed, Reformed authors later pointed to this as evidence that the early Christians understood a symbolic dimension. However, context is crucial: Tertullian was arguing against Marcion’s docetism (the belief that Christ’s body was unreal or purely spiritual). His point is that Christ had a real human body, so real that it could be given under a visible “figure” like bread. “A figure there could not have been, unless there were first a veritable body”, he argues (Real presence of Christ in the Eucharist - Wikipedia). In other words, Jesus saying “this is My body (given for you)” with bread proves He considered His body a tangible reality (else the analogy is meaningless). Tertullian’s use of “figure” here does not deny the bread’s connection to Christ’s body; rather, he’s emphasizing that the Eucharist truly signifies Christ’s real flesh, countering those who would call Christ’s body a phantasm (Real presence of Christ in the Eucharist - Wikipedia). In other writings, Tertullian speaks of the Eucharist in very concrete terms: he refers to the Eucharistic bread as “the Lord’s body” and even says after receiving it, a Christian “feeds on the richness of the Lord’s body” (What the Early Church Believed: The Real Presence | Catholic Answers Tract). He also draws an analogy: just as baptism cleanses the body so the soul is washed, “so, in the Eucharist, the flesh feeds on Christ’s Body and Blood so that the soul may be filled with God” (What the Early Church Believed: The Real Presence | Catholic Answers Tract). Clearly, Tertullian assumes that Christ’s body and blood are truly present to be consumed by the faithful. Yet he can call the bread a “figure.” This simply reflects the early Church’s comfortable use of sacramental language: a sacrament is a sign (figure, symbol) which truly contains and confers the reality it signifies. Catholic theology later would formalize this (the concept of “sacramentum et res” – the outward sign and the inward thing). Reformed theology also agrees that the bread is a sign, but Calvin would stress that it more than signifies – it is a means by which the Spirit truly gives what is signified. In that sense, Tertullian stands in agreement with both sides: the Eucharist is a sign (so one must not imagine a crude eating of Christ’s flesh as cannibalism), but it is a sign that delivers the reality (Christ’s true life) to the receiver.

Another major voice is Origen of Alexandria (c. 184–253), a learned biblical scholar. Origen richly allegorized Scripture and at times spoke of the Eucharistic elements in symbolic terms. For example, in Contra Celsum he refers to “the bread which we call the Eucharist” as a “symbol of gratitude to God” (Origen - Against Celsus - Book VIII - Search Early Christian Writings). Some have cited this to claim Origen thought the Eucharist was merely symbolic. However, Origen elsewhere affirms the sacredness of the Eucharist and the need to treat it with reverence. He distinguished between the “material bread” and the “spiritual food” it becomes. In a homily on Exodus, Origen says the manna prefigured “the bread of life… which the priesthood consecrates by word and prayer”. Origen emphasizes that the faithful should not partake of the Eucharistic bread unworthily or in sin, indicating he believed it truly holy. So Origen, like other Fathers, combines realism with symbolic description. He calls the Eucharist symbol and mystery, yet insists it conveys divine life. This interplay would later be seen in Augustine as well.

By the early 3rd century, the structure of Eucharistic worship and its ministerial context was well established. St. Cyprian of Carthage (d. 258), for instance, writes about the Eucharist as a sacrifice offered by priests, and he insists on using wine mixed with water in the cup (seeing the mixture as symbolizing the unity of Christ with his people). Cyprian calls the Eucharist “the sacrifice of the Lord” and argues that “if Jesus Christ, our Lord and God, is Himself the High Priest of God the Father; and if He offered Himself as a sacrifice to the Father… then certainly the priest truly acts in the place of Christ when he reproduces what Christ did, and he offers a true and complete sacrifice in the Church to God the Father” (Epistle 63). This shows a developing understanding of the priesthood and sacrificial nature of the Eucharist – ideas that would become defining for the Catholic view. Protestants would later reject the notion of the Eucharist as a propitiatory re-sacrifice, but here in the 3rd century the groundwork is being laid for the concept of the Mass as a sacrifice (albeit one with its efficacy derived entirely from Christ’s one sacrifice).

To sum up 150–325 AD: The dominant view remained that the Eucharist is truly the body and blood of Christ, now further explicated as a mystical change in the bread and wine effected by the consecration prayer. Christians like Irenaeus and Cyprian also increasingly described the Eucharist in sacrificial terms and integrated it into an ecclesiology of priesthood. There was no radical doctrinal shift in this period away from earlier belief – rather a deepening. As one modern source puts it, “the early Church Fathers interpreted [Scripture’s words on the Eucharist] literally” (What the Early Church Believed: The Real Presence | Catholic Answers Tract) and “their teaching on Christ’s Real Presence was overwhelmingly realist”. Thus, a Christian of 300 AD in, say, North Africa or Gaul would have recognized the Eucharist as the literal “Body of the Lord” (to be adored and handled with fear and love), even if they also understood it to be a sacrament (a sacred sign veiling spiritual reality).

From a Catholic perspective, this period provides substantial support: later Catholic doctrine sees itself in continuity with these Fathers. For example, the Council of Trent in the 16th century would quote Ambrose, Augustine, and others from slightly later in this era as authorities for the real presence and the change in the elements. The Catholic Church’s emphasis on Tradition is exemplified here – these patristic writings are part of the Church’s memory and authority. Indeed, Trent claimed that the Church “has always retained” this doctrine from Christ and the apostles onward (General Council of Trent: Thirteenth Session - Papal Encyclicals). Looking at 150–325 AD, one can largely affirm that claim: there is no evidence of an orthodox father denying the real presence. Calvinists, on the other hand, while acknowledging the Fathers’ realism, argue that the philosophical explanation (transubstantiation) and certain practices (like adoration of the Host, or the idea of an internal sacrifice) were not present yet but are later medieval additions. They often point out that some Fathers (like Tertullian, Origen, even Augustine slightly later) used “sign” and “figure” language – suggesting that if those Fathers had been asked to endorse Transubstantiation (in the Aristotelian sense of the substance of bread changing), they might not have understood or agreed with that precise concept. Calvin himself, in defending his view, cited earlier Fathers to show that the sign (bread) and the thing signified (Christ’s body) were often distinguished in patristic theology – thereby arguing that his differentiation between the physical bread and Christ’s spiritual presence was not foreign to the early Church ( John Calvin: Institutes of the Christian Religion - Christian Classics Ethereal Library ) ( John Calvin: Institutes of the Christian Religion - Christian Classics Ethereal Library ).

Nonetheless, what is inescapable is that all these early sources show a unified belief in the real, supernatural presence of Christ in the Eucharist. This forms a continuous line into the next era, where this belief would be further clarified especially in response to new debates and the formalization of Christian doctrine after Constantine.

Post-Nicaea to the Reformation

From the 4th century through the medieval era (325–1500s), Eucharistic theology underwent significant development. This millennium can be broadly divided into the Patristic “golden age” (4th–5th centuries), the Early Medieval period (6th–10th centuries), and the High Middle Ages up to the eve of Reformation (11th–15th centuries). Throughout these phases, the dominant trajectory was toward an ever more explicit articulation of the real presence and the nature of the Eucharistic change, as well as the firm establishment of the Eucharist as the central sacrifice of Christian worship. By the end of this period, the Roman Catholic Church (both Western Latin and, with some differences in expression, the Eastern Orthodox Church) had a fully developed doctrine: the bread and wine are changed in substance into the body and blood of Christ (the term transubstantiation is adopted in the 13th century), Christ is wholly present (Body, Blood, soul and divinity) under each species, and the Mass is a true and propitiatory sacrifice (a re-presentation of Calvary). John Calvin’s perspective does not emerge until the 16th century, but in this long interim there were a few voices that in retrospect anticipated some points of his (for example, critiques of overly material interpretations or insistence on the role of faith). In this section, we trace key landmarks: the Fathers of the 4th–5th centuries like St. Ambrose and St. Augustine, the Byzantine insights (e.g. Cyril of Jerusalem, John Chrysostom), the medieval controversies (the 9th-century debate of Radbertus vs. Ratramnus, the 11th-century controversy with Berengar of Tours), the codification of transubstantiatio in the 1215 Fourth Lateran Council, and the Scholastic synthesis in St. Thomas Aquinas. We will see that while the Catholic doctrine was solidifying, there were undercurrents of simpler “spiritual” interpretation that were generally suppressed but would resurface in the Reformation. We will also examine how appeals to Scripture vs. Tradition played out – noting that the medieval Church increasingly leaned on church authority (councils, popes, scholastic doctors), which Protestants later viewed as a departure from Scripture.

The Patristic Era (4th–5th Centuries)

After Christianity became legally recognized in the Roman Empire (Edict of Milan, 313 AD), theological reflection flourished. The great ecumenical councils addressed Trinitarian and Christological issues, not directly the Eucharist, but the era’s leading bishops and catechists did expound on the Eucharist in their teaching of the faithful. St. Cyril of Jerusalem (c. 350), in his Mystagogical Catecheses given to new Christians, speaks plainly: “Do not regard the bread and wine as ordinary food and drink,” he instructs; by the invocation of the Holy Spirit, “they become the Body and Blood of Christ.” He urges the communicants to “approach the altar* not with stretched-out palms and fingers apart, but making your left hand a throne for your right, which is about to receive the King”*, indicating the deep reverence due to the consecrated elements. Cyril even says if one’s sense perceptions suggest only bread and wine, one must trust faith: “Judge not the reality by taste,” he writes, “but be fully assured by faith, not doubting that you have been deemed worthy of the Body and Blood of Christ.” (Catechesis 22). This strong realism and the call to adore Christ in the Eucharist are entirely consistent with Catholic doctrine.

In the Latin West, St. Ambrose of Milan (d. 397) provides one of the clearest pre-medieval descriptions of Eucharistic transformation. Teaching newly baptized Christians, Ambrose writes: “Perhaps you may say, ‘I see something else; how can you assert that I receive the Body of Christ?’ ... I shall prove that this is not what nature formed, but what the blessing consecrated. And the power of the blessing is greater than that of nature, because by the blessing nature itself is changed” (Real presence of Christ in the Eucharist - Wikipedia) (Real presence of Christ in the Eucharist - Wikipedia). He then reminds them of biblical miracles: “For that sacrament which you receive is accomplished by the word of Christ. If the word of Elijah had power to bring down fire from heaven, shall not the word of Christ have power to change the natures of the elements?… Before consecration it is bread; after the words of Christ, it is the Body of Christ. Before consecration, it is wine; after consecration, it is Christ’s Blood.” (Real presence of Christ in the Eucharist - Wikipedia) (Real presence of Christ in the Eucharist - Wikipedia). Ambrose’s teaching is astonishingly close to what later theology would call transubstantiation: a change of the inner nature of bread and wine into Body and Blood, even as the external appearances remain. He explicitly says “what you see is one thing, but what you receive is another” – i.e., sense perception vs. reality differ after consecration. He even encourages the faithful to say “Amen” to this mystery, thereby assenting in faith that it is true (Real presence of Christ in the Eucharist - Wikipedia). Ambrose’s authority in the medieval and Counter-Reformation Church was high; Trent cites Ambrose in affirming the change of the substance by Christ’s word (SUMMA THEOLOGIAE: The change of bread and wine into the Body and Blood of Christ (Tertia Pars, Q. 75)) (SUMMA THEOLOGIAE: The change of bread and wine into the Body and Blood of Christ (Tertia Pars, Q. 75)). For Catholic theology, Ambrose is an important patristic witness that the early Church did conceive of a complete conversion of the elements (even if the philosophical terminology of “substance/accidents” came later). For the Calvinist perspective, Ambrose’s words also pose a challenge – they seem to endorse a miraculous change in the elements that Calvin denied. Calvin might interpret Ambrose’s “change of nature” as describing what the elements become in function or use (consecrated to be means of Christ’s body) rather than an Aristotelian substantial change – but the plain sense of Ambrose is that the bread is transformed by Christ’s word into something else. Thus Ambrose firmly tilts toward the Catholic side of the later divide.

St. Augustine (354–430), the immensely influential bishop of Hippo, wrote extensively on the Eucharist, and his thoughts are subtle. Both Catholic and Reformed traditions claim Augustine’s support, and indeed one finds in his writings material agreeable to both. On one hand, Augustine unequivocally held that the consecrated elements, though visible and tangible as bread and wine, become the body and blood of Christ. Preaching on the Eucharist, he said: “The faithful know what I’m talking about; they know Christ in the breaking of bread. It isn’t every loaf of bread, you see, but the one receiving Christ’s blessing, that becomes the body of Christ” (Real presence of Christ in the Eucharist - Wikipedia). He also taught that worship is due to Christ in the Eucharist: “No one eats that flesh, unless he has first adored it; we do not sin by adoring, but we would sin by not adoring”, he wrote (Dominus est (English)) (Enarrations on Psalm 98). Such statements strongly affirm the Real Presence – the blessed bread becomes Christ’s body, and hence is worthy of adoration (latria). In another sermon (Sermon 272), Augustine addresses the neophytes: “What you see is the bread and the chalice; that is what your eyes report. But your faith must be instructed that the bread is the body of Christ, the chalice is the blood of Christ.” This is a straightforward literal identification.

On the other hand, Augustine is equally famous for his symbolic and ecclesial interpretation of the Eucharist. He emphasized that the sacrament signifies the unity of the Church (many grains become one bread, as in 1 Cor 10:17) and that the true eating is done by faith. In his Tractates on the Gospel of John (Tractate 25), commenting on “eat my flesh, drink my blood” (John 6), Augustine remarks that this is a figure of speech: “Understand figuratively what I have said,” Christ explains, “you are not to eat this body which you see, nor to drink that blood which those who crucify me will spill. I have commended to you a certain mystery; spiritually understood, it will give you life” (SUMMA THEOLOGIAE: The change of bread and wine into the Body and Blood of Christ (Tertia Pars, Q. 75)) (SUMMA THEOLOGIAE: The change of bread and wine into the Body and Blood of Christ (Tertia Pars, Q. 75)). Augustine concludes: “Believe, and you have eaten”. This is a crucial quote that Reformed theologians (including Calvin) have loved to cite, as it underscores the role of faith in partaking of Christ. Augustine is saying that the physical chewing (manducation) of Christ’s literal flesh profits nothing without the Spirit; the real eating is believing in Him. Augustine also called the Eucharist at times the “sign” or “sacrament” of Christ’s body and blood – which is true in Catholic theology as well, but Protestants highlight it to show Augustine’s awareness of symbolism. Did Augustine deny the Real Presence? No – he clearly believed Christ is truly given in the sacrament. But he did think in a nuanced way: the bread “is” Christ’s body in the sense that it communicates Christ’s body to the Church, and he tended to stress the effect (being united to Christ in faith and charity) over the metaphysical mechanism.

One of Augustine’s striking images is that Christ “carried Himself in His own hands” when He said “This is My body” (referring to the Last Supper; Enarration on Psalm 33). This poetic statement again presupposes that Christ identified the bread with His body. Augustine also affirmed that even unworthy recipients receive Christ’s body and blood (though to their peril), which implies the objective presence is there regardless of the recipient’s faith – aligning with Catholic teaching and even with Calvin’s acknowledgment that the unworthy are offered Christ (though Calvin would say they don’t beneficially receive Him) (Real presence of Christ in the Eucharist - Wikipedia).

In summary, Augustine’s legacy provided ample material for both sides of the later debate: Catholics draw on his realist and devotional statements (and indeed medieval Latin theology, heavily influenced by Augustine, remained firmly realist), whereas Reformers drew on his insistence on spiritual understanding and the primacy of faith. This dual aspect is captured by a later quote often attributed to Augustine: “No one bears away from this Sacrament more than is gathered with the vessel of faith” (Real presence of Christ in the Eucharist - Wikipedia) – meaning the effect of Communion depends on one’s faith. Calvin loved this quote (which he paraphrases from Augustine) (Real presence of Christ in the Eucharist - Wikipedia), using it to argue that faith is the means by which we truly partake of Christ, not a corporeal chewing. Yet the Catholic would agree that faith is necessary to receive grace from the sacrament (one who eats without faith receives Christ’s presence but not His saving grace, rather condemnation per 1 Cor 11:29). Thus Augustine bridges: he does not negate the Real Presence at all, but he centers the mystery on spiritual communion and charity (he famously said the Eucharist is the “sacrament of love, sign of unity, bond of charity”).

By the close of the patristic era (5th century), the “dominant theological view” on the Eucharist in the universal Church was a realistic-sacramental one: the Eucharist is the body and blood of Christ, a change occurs at consecration (though not analyzed in Aristotelian terms yet), and it is to be adored and received with faith for the forgiveness of sins and eternal life. The Catholic position is essentially this view carried forward, and would only clarify further in medieval scholasticism. The seeds of later divergence were present only in embryo: e.g., different emphases (literal vs. symbolic language) that would later be amplified. Importantly, there was no concept of sola Scriptura guiding Eucharistic theology – the Church fathers freely used Scripture, yes, but within the context of the Church’s rule of faith and tradition. By 400 AD, one could not find a single Father arguing “the Bible says ‘Do this in remembrance’, therefore it’s just a symbol” – that kind of argument appears only in the 16th-century Reformation. The Fathers overwhelmingly read Scripture’s Eucharistic passages literally and relied on the inherited liturgical practice as authoritative. For instance, St. Basil (d. 379) notes that many unwritten practices (like certain prayers) are followed in the Church as having apostolic origin (On the Holy Spirit, ch. 27). This coherence of Scripture and Tradition is a hallmark of the Catholic approach, and history shows it in action during this era.

The Early Medieval Period (6th–10th Centuries)

After Augustine, Western theology went through a somewhat quieter period until the Carolingian renaissance. The Eucharistic doctrine continued in practice (with profound reverence and belief in the real presence maintained in monastic and lay devotion), but few new theological treatises were written for a while. By the 9th century, however, we encounter the first explicit theological controversy on the Eucharist within the Western Church – a sign that doctrinal curiosity was awakening.

This is the Paschasius Radbertus vs. Ratramnus debate in the 800s under Carolingian emperor Charles the Bald. Paschasius Radbertus, a monk of Corbie, wrote On the Body and Blood of the Lord (831 AD) for Charlemagne’s grandson. He argued in very realist terms that after consecration, “nothing else than Christ’s body and blood” is present – the same body born of Mary and sacrificed on the cross (albeit in a mystical way). Radbertus emphasized identity: the Eucharistic body is identical to Christ’s historical body (though invisible to eyes, perceived by faith). In response, Ratramnus (another monk of Corbie, possibly at the behest of the King) wrote a treatise (c. 833) taking a different position. Ratramnus distinguished the “external appearances” of bread and wine from the “inner truth” of Christ’s body and blood. He agreed that the Eucharist is in a mystery Christ’s body and blood, but he stressed that it is not Christ’s body “in the literal and physical sense” but “in figure, in mystery, in power” (Real presence of Christ in the Eucharist - Wikipedia) (Real presence of Christ in the Eucharist - Wikipedia). He famously answered that the faithful receive the body of Christ “in mystery (in mysterio)” not “in literal truth (in veritate)” (Real presence of Christ in the Eucharist - Wikipedia) – meaning not in the way our senses would conceive of eating flesh, but in a spiritual reality veiled under the sacrament. He did not deny the Real Presence; rather, he opposed what he saw as a “Capharnaitic” or grossly material interpretation (evoking John 6 where Jews asked “how can he give us his flesh to eat?”). Ratramnus maintained that after consecration the outward aspects of bread and wine remain, and if one examines without faith, it appears nothing has changed; only through faith does one discern Christ’s body present (Real presence of Christ in the Eucharist - Wikipedia) (Real presence of Christ in the Eucharist - Wikipedia). He used the term “figura” and “symbol” in a way reminiscent of earlier writers, and he implied that the wicked do not consume Christ in the sacrament, since they lack the faith that discerns Christ.

The outcome of this Carolingian debate was interesting: Paschasius’s view (the more “literal” real presence) gradually prevailed in influence, becoming standard in the medieval Church, while Ratramnus’s treatise was not condemned but remained a minority perspective. In hindsight, we can see Paschasius Radbertus’s theology as an early statement of what would become the Catholic position, and Ratramnus’s as somewhat closer to a Calvin-like position – acknowledging a true presence “in power” or effect, but insisting that the res (reality) of the sacrament is not to be understood in mundane physical terms. Indeed, Ratramnus’s language (“in figure, mystery, power”) matches well with Calvin’s notion of a “spiritual presence” and the idea that the sign and thing signified are not absolutely one and the same (Calvin often said the signs are called by the name of the thing signified, e.g. the bread “is” Christ’s body sacramentally (Chapter 29.5, 6 - Reformation 21)). However, an important caveat: Ratramnus still believed in a form of Real Presence – he was not a Zwinglian far removed from Catholic doctrine. Some scholars say Ratramnus might have anticipated a “spiritual reception” theory where only believers receive the Body of Christ, whereas Radbertus taught that Christ’s body is objectively present in the elements regardless of the recipient (which is closer to Catholic teaching that even unworthy communicants consume Christ, albeit to their own judgment, as per St. Paul). The debate shows that the medieval Church was wrestling with how to articulate the Eucharistic mystery, even though both sides accepted the fundamental reality of Christ’s presence.

Moving forward, by the 11th century, the issue arose again with more intensity in the person of Berengar of Tours (c. 1000–1088). Berengar was a French theologian who, influenced by Augustine and possibly Ratramnus’s writing, argued against the idea of a material change in the Eucharist. He held that the bread and wine remain in their substance and that Christ’s body is received spiritually by faith. He famously said that the Eucharist is efficacious as a sacrament but one should not assert a change in the elements such that one could chew Christ’s flesh with the teeth. Berengar’s teachings caused a stir, as by this time the prevailing mindset, especially among the faithful and local clergy, was quite literal in venerating the consecrated host. Several Church councils condemned Berengar’s view. Under pressure, Berengar signed statements (e.g. the Council of Rome 1079) affirming that “the bread and wine, after consecration, are converted into the true and proper and life-giving flesh and blood of our Lord”, and that this is sensed “not only sacramentally but in reality and truth.” He later recanted again, and the controversy persisted until his death, but ultimately the Church sided firmly with the realist interpretation. This episode basically settled that Western orthodoxy would henceforth explicitly teach a conversion (conversio) of the elements. The term “transubstantiation” was not yet dogma, but was increasingly used by theologians in the 12th century (e.g. Hildebert of Lavardin, 1110s) to describe this miraculous change.

It is notable that Berengar’s objections foreshadow Reformation-era arguments: an appeal to reason and common sense (e.g. bodies cannot be in multiple places, Christ’s body is in heaven, etc.), an appeal to authority of earlier writers like Ratramnus or Augustine’s spiritualizing passages, and an aversion to what seems a “magical” or carnal idea. Berengar reportedly invoked Aristotelian ideas of substance and accident to argue that accidents (appearance) cannot exist without substance, so if the bread’s accidents remain, its substance must remain. Ironically, it would be via Aristotelian metaphysics that the Church later formulated the solution: that the accidents can remain without the substance by God’s power, and the substance is changed (this is precisely the definition of transubstantiation). So, in a way, Berengar forced the Church to clarify doctrine using philosophy. His stance was essentially an outlier in medieval Catholicism, and after his condemnation there was little open dissent until the Reformation. However, some sects (like the Wycliffites/Lollards in the 14th century and the Hussites in the early 15th) would echo similar skepticism about transubstantiation, showing a continuity of that minority thread.

The High Middle Ages and Scholastic Definition (12th–15th Centuries)

By the 12th and 13th centuries, medieval scholastic theologians systematized doctrine. The Fourth Lateran Council in 1215 was a pivotal moment: it promulgated: “Jesus Christ’s body and blood are truly contained in the sacrament of the altar under the forms of bread and wine, the bread being transubstantiated into the body and the wine into the blood by divine power” (Real presence of Christ in the Eucharist - Wikipedia). This is the first official use of “transubstantiated” in a creed or council. The choice of this word indicates the Church’s commitment to a metaphysical realism about the change: substance (the inner reality) is converted, while species (the appearances) remain. This articulation answered Berengar’s challenge and any lingering ambiguity.

Soon after, St. Thomas Aquinas (1225–1274) gave the classic theological exposition in his Summa Theologiae. Aquinas affirmed with subtlety that Christ becomes present in the Eucharist by transubstantiation – a unique change that is “entirely supernatural”. He argued: “The presence of Christ’s true body and blood in this sacrament cannot be detected by sense, nor understanding, but by faith alone, which rests on Divine authority.” (SUMMA THEOLOGIAE: The change of bread and wine into the Body and Blood of Christ (Tertia Pars, Q. 75)) Faith, founded on Christ’s words, assures us of what senses cannot perceive. He confronted objections like those of Berengar: for example, to the objection “the substance of bread must remain, otherwise an accident (taste, shape) would exist without a subject,” Aquinas responded that indeed the remaining accidents have no subject but are miraculously upheld by God’s power (SUMMA THEOLOGIAE: The change of bread and wine into the Body and Blood of Christ (Tertia Pars, Q. 75)) (SUMMA THEOLOGIAE: The change of bread and wine into the Body and Blood of Christ (Tertia Pars, Q. 75)). He stated it is heretical to deny that a conversion of substance occurs (SUMMA THEOLOGIAE: The change of bread and wine into the Body and Blood of Christ (Tertia Pars, Q. 75)). Aquinas also delineated that Christ’s body is not present in the normal mode of a body (dimensive quantity in space), but “sacramentally” present – meaning whole and entire under each part of the appearances, without extension. This avoids the idea of local motion or that Christ’s body leaves heaven (Calvin later will essentially accept that part: he also insists Christ’s body remains in heaven and does not descend into the elements locally; the difference is Aquinas says the substance of bread changes into the substance of Christ’s body, whereas Calvin says the bread remains bread and Christ’s body stays in heaven, with the Spirit bridging the gap). In short, Aquinas gave the most robust intellectual defense of the Catholic view, integrating Scripture (“This is My Body” taken at face value) with Aristotelian ontology to explain how such a thing is possible without violating reason (albeit involving miraculous exception to normal natural law).

By late Middle Ages, the Catholic doctrine was firmly established: the Council of Constance (1415) even condemned the Wycliffite proposition that “bread remains bread after consecration” as heresy. The Eucharist was also at the center of popular piety – with practices like elevation of the Host (introduced in the 13th century), Corpus Christi processions, and devotional literature. All these presume a strong belief that Christ is corporally present under the sacrament.

It’s worth noting the Eastern Orthodox Church during this time held an equivalent belief in the Real Presence, often preferring terms like “metousiosis” (change of being) later on. In 1672 their Synod of Jerusalem explicitly affirmed something very akin to transubstantiation, though generally the East was content to regard it as a holy mystery without tightly defined philosophical language. For our East-West comparative, suffice it to say that Calvin’s view would have been alien to both sides in the medieval millennium. The entire Christian world, save a few dissidents, confessed that in the Eucharist the bread truly becomes and is Christ’s body. The major lingering difference was how to conceptualize it (a change of substance or a more ineffable sacramental union).

Thus, on the eve of the Protestant Reformation (early 1500s), the “dominant theological view” was unambiguously the Catholic one: transubstantiation and Eucharistic sacrifice. The Church taught it as de fide; the faithful attended Mass believing a miracle happened on the altar at the words of consecration; theologians like Gabriel Biel reiterated Aquinas’s teachings; and any contrary voice was suppressed. This was the doctrine codified at the Council of Trent (1545–1563) in response to the Reformers. Trent, essentially summarizing the medieval consensus, declared: “By the consecration of the bread and wine, a conversion is made of the whole substance of bread into the substance of the Body of Christ our Lord, and of the whole substance of wine into the substance of His blood; which conversion is aptly and properly called by the Catholic Church Transubstantiation* (General Council of Trent: Thirteenth Session - Papal Encyclicals). It pronounced anathema on anyone denying that “the body and blood of Christ together with His soul and divinity… is truly, really, and substantially contained in the sacrament” or asserting that only the “sign or figure” is present (General Council of Trent: Thirteenth Session - Papal Encyclicals) (General Council of Trent: Thirteenth Session - Papal Encyclicals). Trent saw itself as ratifying the “true and ancient doctrine” always held (General Council of Trent: Thirteenth Session - Papal Encyclicals), and indeed, our historical survey thus far shows a broad continuity from the early Church to the 16th century on the core of that doctrine, albeit articulated increasingly explicitly.

From a comparative perspective, by 1500 the divergence between what would become Catholic vs. Calvinist views was latent but not yet actualized in any official way. The Church’s position was essentially fixed in the Catholic mold. The proto-Reformers (Wycliffe, Hus) who questioned aspects of it were condemned. Calvin’s perspective thus enters as a protest against this dominant trajectory, claiming it went beyond Scripture and early tradition. The assumptions also differed: the medieval Catholic approach trusted the Church’s authority to define dogma and develop doctrine (even using non-biblical terminology like “transubstantiation” because it was seen as a logical unpacking of biblical truth). The Reformers would operate on sola Scriptura, rejecting terms and concepts not found in the Bible. For example, Calvin would argue that the word transubstantiation “neither the Scriptures nor the ancient fathers ever used,” calling it a “philosophical fiction” imposed on a mystery (A Prelude on the Babylonian Captivity of the Church (1520)) (A Prelude on the Babylonian Captivity of the Church (1520)).

Indeed, Martin Luther (1483–1546) – whose reforming career began in 1517 – initially accepted the real presence fully and even in 1520 wrote against “sophistical” transubstantiation, not because he denied the Real Presence, but because he thought it unnecessary to go beyond This is My Body. Luther considered transubstantiation an over-sophistication; he was open to the idea that Christ’s body coexists with the bread (what later Lutherans termed “sacramental union” rather than a conversion of substance) (Luther vs. Zwingli 2: Luther on the Lord's Supper). But crucially, Luther vehemently upheld that Christ’s words are true: “This is my body” – Christ’s body is truly given to all who partake. He parted ways with Catholicism on the conceptual explanation and the sacrificial dimension of the Mass (which he saw as a blasphemous denial of the sufficiency of the Cross) (Luther vs. Zwingli 2: Luther on the Lord's Supper), but not on the reality of Christ’s presence. In fact, Luther’s stance against more radical reformers (like Zwingli) was so strong that at the Marburg Colloquy (1529) he famously refused fellowship with the Swiss over this issue, insisting on the literal meaning of Hoc est corpus meum. Luther quipped he’d rather drink blood with the Pope than mere wine with Zwingli – underlining how important the Real Presence was to him. So ironically, Luther remained close to the medieval belief, only tweaking the explanation (rejecting the idea that the bread’s substance is gone – he thought Christ’s body is present “in, with, and under” the bread).

John Calvin (1509–1564), however, representing the second generation of Reformers and the founder of the Reformed/Calvinist branch, sought a middle path that retained real presence in a spiritual manner. Calvin admired Luther’s desire to take Christ’s words seriously and to see the Supper as God’s action and a true means of grace. But he also shared with other Reformers the conviction that Christ’s body is localized in heaven (per Acts 3:21, Christ must remain in heaven until the last day) and that it does not literally descend or get chewed. Thus he found the Lutheran notion of bodily ubiquity or in/beneath the bread problematic. Calvin’s solution was to shift the mode of presence to the Holy Spirit: the Spirit bridges the gap between the ascended Christ and the believers on earth. In Calvin’s theology, when the faithful receive the consecrated bread and wine, the Holy Spirit truly unites them to Christ in heaven, communicating Christ’s real body and blood to their souls (a “real feeding” on Christ). Calvin phrased it eloquently: “The Spirit truly unites things separated in space” – i.e., the Spirit makes the distance between Christ’s body (in heaven) and us (on earth) of no effect (Real presence of Christ in the Eucharist - Wikipedia). We genuinely partake of the one Jesus. Calvin writes: “The flesh and blood of Christ are no less truly given to the unworthy than to God’s elect believers,” but only believers receive them fruitfully (Real presence of Christ in the Eucharist - Wikipedia). The Westminster Confession of Faith (1646), a century later, distilled the Reformed view by stating that Christ’s body and blood are present in the Supper “not corporally or carnally, in, with, or under the bread and wine, but spiritually present to the faith of believers” (The Oxford Handbook of Presbyterianism 9780190608408 ...). And that the bread and wine remain “in substance and nature… truly and only bread and wine”, though sacramentally they represent Christ (Chapter 29.5, 6 - Reformation 21). This is essentially Calvin’s position canonized.

Calvin, of course, went to Scripture as the primary source. He interpreted “This is My body” in the context of Jesus also saying “I am the door,” etc., meaning the verb “is” can signify “represents” or “is sacramentally united to”. He heavily emphasized John 6 in a spiritual sense (Augustine’s “believe and you have eaten” argument). He also appealed to the Church Fathers to show that they did not intend crude physical presence. For instance, Calvin quotes Augustine’s line that Christ warned against understanding eating His flesh in a carnal way (SUMMA THEOLOGIAE: The change of bread and wine into the Body and Blood of Christ (Tertia Pars, Q. 75)), and that the true eating is by the soul’s faith (SUMMA THEOLOGIAE: The change of bread and wine into the Body and Blood of Christ (Tertia Pars, Q. 75)). Calvin frequently cited the Fathers like Chrysostom, citing passages where they speak of “spiritual matter” or “faith as the means of eating.” He was keen to demonstrate that the Reformed view was not an innovation but consistent with the best of early tradition properly understood ( John Calvin: Institutes of the Christian Religion - Christian Classics Ethereal Library ) ( John Calvin: Institutes of the Christian Religion - Christian Classics Ethereal Library ). Nonetheless, Calvin’s view was a clear break from the medieval Catholic/Orthodox consensus on several points: rejection of transubstantiation (which he called “an absurdity”, “a figment” without biblical basis (A Prelude on the Babylonian Captivity of the Church (1520))), rejection of the idea of adoration of the Host (since for Calvin Christ’s body is not literally in the bread, to adore the bread would be idolatrous – whereas Catholics, as Trent affirmed, hold that Christ, whole God and man, is present and thus adoration or latria is due to the Sacrament (General Council of Trent: Thirteenth Session - Papal Encyclicals)), and rejection of the Mass as sacrifice (Calvin saw the Eucharist strictly as a gift from God to us, a “testament”, and our response of thanksgiving; offering Christ anew was to him an affront to the sufficiency of the cross (Luther vs. Zwingli 2: Luther on the Lord's Supper)). Calvin did preserve the language of “sacrifice of praise” and self-offering – he said in the Supper we offer ourselves in thanksgiving, a notion also present in Augustine and not denied in Catholic teaching (Catholics also say the Mass includes the Church offering herself along with Christ). But Calvin (and all Protestants) categorically denied any propitiatory aspect to the Eucharist.

When comparing Catholic vs. Calvin’s theology from the Reformation onward, we see a number of key contrasts crystallize:

• Nature of the Change: Catholics assert a change of the elements’ substance (transubstantiation), so that Christ is corporeally, substantially present under the appearances. Calvin denies any change in the elements’ substance – the bread remains bread (hence can be disposed of ordinarily) (Real presence of Christ in the Eucharist - Wikipedia). For Calvin, the bread becomes a spiritual instrument: it remains bread, but when taken with faith, Christ uses it to feed the soul with His body. Thus, presence is not in the elements themselves, but in the action of Communion – the Holy Spirit unites the sign and the thing signified in the moment of reception for believers. (Westminster: the bread *“has such relation to Christ crucified, that truly, yet sacramentally only, it is called Christ’s body,” while still being bread in substance (Chapter 29.5, 6 - Reformation 21).)

• Objectivity vs. Subjectivity of Presence: In Catholic doctrine, Christ’s presence in the Eucharist is objective and enduring – as soon as consecration occurs, Christ is present regardless of anyone’s faith, and remains present as long as the appearances remain (hence practices like reserving the Sacrament in a tabernacle, Eucharistic adoration, etc., all of which Calvin rejected). In Calvin’s view, Christ’s presence is dynamic and relational – “really present to faith” (The Oxford Handbook of Presbyterianism 9780190608408 ...). Unbelievers who eat receive only bread and wine (and if they persist in unbelief, they eat judgment to themselves for profaning the ordinance, but they do not actually receive Christ’s life-giving flesh). Calvin did write, as noted, that Christ’s flesh is offered even to the unworthy, but they lack the “vessel” of faith to receive it, so effectively they get no benefit (Real presence of Christ in the Eucharist - Wikipedia). In Catholicism, even an unworthy communicant consumes the true Body of the Lord (and thus commits sacrilege). This difference ties to the underlying theology of efficacy: for Catholics the sacraments work ex opere operato (by the very fact of the act, God’s grace is present, though to bear fruit the person must cooperate), whereas for Calvin, the sacraments have no power in themselves – their power lies in the Holy Spirit’s action and the faith of the recipient.

• Sacrifice and Soteriology: The Catholic position sees the Mass as the same sacrifice as Calvary made present in an unbloody manner – a doctrine definitively taught at Trent. For Calvin, this was anathema; he believed Christ’s one sacrifice cannot be repeated or re-presented, and the Lord’s Supper is a meal, not a sacrifice (except in the sense of our sacrifice of praise). This has implications: in Catholicism the priest is an alter Christus offering sacrifice; in Calvin’s churches, the minister is not a sacrificing priest at all, just a minister of Word and Sacrament, and the focus is on the congregation receiving, not offering. This particular divergence goes beyond the scope of presence but is central in comparing confessional perspectives.

• Scriptural warrant and Authority: Catholics argue that Christ’s words “This is My Body… This is My Blood” (in the Synoptics and 1 Cor 11) and John 6 (“My flesh is true food…”) are straightforward and that the unanimous tradition of the Church from the earliest times supports a literal interpretation (What the Early Church Believed: The Real Presence | Catholic Answers Tract) (What the Early Church Believed: The Real Presence | Catholic Answers Tract). Catholic apologists often quote Ignatius, Justin, Ambrose, etc., to show continuity. They also rely on the Church’s magisterium (e.g., Trent) as authoritative, believing the Holy Spirit guides the Church into truth even through development of doctrine. Calvinists, by contrast, hold Scripture alone as the final authority. They would contend that the Catholic interpretation reads later theological ideas into Scripture. Calvin himself tackled John 6 and the Last Supper texts in depth, coming to a sacramental-symbolic reading: e.g., “this cup is the new covenant in my blood” – clearly “cup” stands for “wine,” and “is” stands for “signifies or seals” the covenant in Christ’s blood; thus, “This is my blood” means “This wine is the sign and instrument of my blood (of my sacrifice).” They point out Jesus often spoke metaphorically (“I am the vine,” “I am the door”). They also note that at the Last Supper Christ’s body and blood were physically still intact before the disciples – so the supper was a pledge of the sacrifice to occur next day, not a literal cannibalistic eating. Catholics respond that Jesus can miraculously offer His body under sacramental form even before the crucifixion (as an anticipatory sign), and that saying “I am the vine” is in a different context, whereas “This is My body” occurs during the institution of a ritual and accompanied by the command to repeat it – language of covenant sacrament rather than parable. Thus, both sides use Scripture but interpret it through different lenses – one with a preference for literal-liturgical sense and the backing of continuous tradition, the other with a preference for spiritual-metaphorical sense and a view that the plain literal sense in context points to a memorial and spiritual feeding rather than a change in elements.

From the Reformation through modern times, these differences have persisted, although there have been efforts at mutual understanding. The Council of Trent (1540s–1560s) firmly fortified the Catholic stance with canons and anathemas (General Council of Trent: Thirteenth Session - Papal Encyclicals), and the Roman Catholic Church has reiterated it in every generation since (e.g., the new Catechism of 1992 states: “In the Eucharist the bread and wine become the Body and Blood of Christ”, quoting Trent (Here is what St. Irenaeus said about the Eucharist)). The Reformed confessions (such as the Belgic Confession of 1561, the Heidelberg Catechism of 1563, and the Westminster Confession of 1646) all codify Calvin’s view and reject Catholic teachings. For instance, the Belgic Confession affirms that “by faith (which is the hand and mouth of our soul) we partake of Christ’s true body and blood through the working of the Holy Spirit”, but also that “the manner… is beyond our understanding – it is spiritual”, and explicitly denies “that the bread and wine change in substance” (Article 35). The Westminster Confession goes so far as to call transubstantiation “repugnant to Scripture and to common sense, overthrowing the nature of the sacrament, and the cause of many superstitions and gross idolatries” (Chapter 29.5, 6 - Reformation 21) – a very strong condemnation from a post-Calvin Calvinist perspective.

Yet, in modern theological scholarship, there has been some rapprochement in tone if not in substance. Many Catholic theologians emphasize the mysterious and supernatural character of the Eucharist – not a “physical” change detectable by science, but a sacramental miracle; this aligns with Aquinas’ view that senses can’t detect it (SUMMA THEOLOGIAE: The change of bread and wine into the Body and Blood of Christ (Tertia Pars, Q. 75)). Some have tried explaining transubstantiation in personalist terms (transignification, etc.), though official teaching still uses the classic term (see Paul VI’s 1965 encyclical “Mysterium Fidei” which reaffirms transubstantiation against those wanting to replace it). On the Protestant side, some theologians have sought a deeper appreciation of the Real Presence beyond Zwinglian memorialism. The 20th-century ecumenical dialogues (like the WCC’s Lima Text 1982 – Baptism, Eucharist and Ministry) resulted in agreed statements that “Christ is present and active in the Eucharist through the Holy Spirit” – wording that both could assent to, albeit interpreting differently. Certain Anglican and Lutheran dialogues with Catholics produced documents showing significant convergence on the meaning of the Eucharist (e.g., the ARCIC documents between Anglicans and Catholics, or the Lutheran-Catholic Dialogue’s agreements on the Real Presence and even on the sacrificial memorial aspect). Reformed churches have been a bit more cautious in such dialogues, given their strong historical confessional statements. However, in 2017, on the 500th anniversary of the Reformation, Catholic, Lutheran, and Reformed representatives together affirmed belief in the real presence of Christ in the Lord’s Supper, even as they acknowledged ongoing differences on explaining it (these were pastoral statements aiming at common Christian witness).

In summary, today the Catholic Church continues to teach what it has for centuries: that in the Eucharist, by the words of Christ and the power of the Holy Spirit, the bread and wine are changed into the Body and Blood of Christ – “the source and summit of the Christian life” in Catholic parlance, and it encourages Eucharistic adoration and frequent communion. Calvinist (Reformed) churches continue to celebrate the Lord’s Supper as one of two sacraments (the other being baptism), usually at regular intervals (monthly or quarterly in some Presbyterian traditions, though some Reformed communities have it weekly). They see it as a means of grace that truly nourishes believers’ union with Christ. While a Reformed minister will use words like “the body of Christ given for you” when distributing bread, Reformed theology would stress that this feeding on Christ occurs in a heavenly and spiritual manner. Contemporary Reformed catechisms and teaching materials maintain Calvin’s emphasis that the Supper strengthens faith by the Holy Spirit’s action, uniting believers to the risen Lord. They usually do not speak of any “change” in the elements; rather, Christ uses the elements to communicate Himself. There is also a greater reticence about Eucharistic devotion outside the liturgical use – for example, you will not find Reformed churches with tabernacles or treating leftover bread/wine as anything but common food (often it is consumed or disposed of quietly, but without ceremony, since once the service is over, the bread is just bread). This contrasts with Catholic (and Orthodox and even Lutheran) practice of reverent consumption or reservation of the Sacrament due to belief in the enduring presence of Christ.

Finally, it’s worth addressing how each side justifies its fundamental assumptions historically. The Catholic reliance on Tradition is bolstered by the patristic witness: as we saw, there is a compelling case that the early church’s faith was essentially “Catholic” in regarding the Eucharist as truly Christ’s body and blood. The Catholic Church argues that the consensus of the Fathers (St. Irenaeus, St. Cyril, St. John Chrysostom, St. Augustine, etc.) supports its doctrine, and that the Church, guided by the Holy Spirit, has the authority to formulate the doctrine (e.g., using the word transubstantiation) in continuity with that apostolic Tradition. From this view, sola Scriptura is seen as insufficient – because one needs the Church to identify the canon of Scripture in the first place and to interpret it rightly. Indeed, no major Father taught “Scripture alone” in the Protestant sense; they all assumed the authority of the Church to teach and the binding nature of apostolic traditions (2 Thess 2:15). The Catholic would point to the Eucharist doctrine itself as an example of a truth that becomes explicit through the Church’s reflection over centuries (much like the Trinity or the two natures of Christ were clarified over time). If one were to rely on Scripture interpreted apart from that living tradition, Catholics argue, one might miss or misconstrue aspects that the early Christians understood in practice.

On the other side, Calvin and the Reformers contended that the medieval Church had accumulated errors by subordinating Scripture to man-made tradition. They saw the elaborate Eucharistic doctrine (and especially the sacrificial role of priests) as one such error. They sought to “renew” the practice more in line (as they thought) with the New Testament and early Church simplicity. Calvin, for instance, often claimed his view had the support of the better sort of Fathers and that it avoided the philosophical speculation the medieval scholastics introduced. He accused the Catholic Church of a kind of “Capernaitic” folly – treating Christ’s flesh in a crude way which Christ himself refuted in John 6 (SUMMA THEOLOGIAE: The change of bread and wine into the Body and Blood of Christ (Tertia Pars, Q. 75)). The Reformers also appealed to reason and common experience: for example, Calvin notes that after the Supper, the consecrated bread is treated as ordinary – it can grow mold, etc., which would be strange if it were actually divine Flesh. (Catholic theology answers that the accidents can decay – if the appearances corrupt, Christ’s presence ceases, since the sign no longer exists to be the sacrament; so a moldy Host is no longer the sacrament, presumably.) Protestant apologists pointed out supposed “absurdities” of transubstantiation – such as Christ’s body being in many places or the appearance of bread existing without a subject. Catholic scholastics had their technical answers, but to the Reformers these were seen as vain scholastic excrescences not warranted by Scripture. Thus, they felt justified in holding only to what they see explicitly taught in Scripture: that we are to eat bread and drink wine in remembrance of Christ, and that this communion is a participation in Christ’s Body and Blood (1 Cor 10:16) – the how is a mystery of the Spirit, but it is not a physical or substantial change.

In evaluating these positions with historical hindsight, one might say: The Catholic position can claim a continuous development from the early church’s faith and worship, preserving both the symbolic and realistic dimensions in a synthesized doctrine (symbol becomes reality). It takes seriously all biblical passages (including “This is My body” and John 6 in a literal sense) and relies on the Church’s teaching authority to navigate theological clarification. The Calvinist position can claim fidelity to the primacy of Christ’s once-for-all sacrifice and a refusal to define mystery beyond Scripture. It harkens to patristic cautions against crass literalism (e.g., Augustine’s advice to understand spiritually) and seeks to center the sacrament on personal faith-union with Christ, which indeed was a key aim of many Church Fathers as well (they constantly urge recipients to approach worthily, with faith and charity, not superstition). Calvinists also often note that some medieval practices had indeed become superstitious (as even Catholic historians would admit, late medieval laity sometimes saw the Mass as a magical spectacle – e.g., just gazing at the elevated Host for a blessing without receiving Communion).

In the end, the theological chasm over the Eucharist between Catholics and Calvinists remains one of the deepest in Christian doctrine. It is not merely about ritual but touches on Christology, ecclesiology, and authority. Each side marshals history to its defense: Catholics point to Ignatius, Ambrose, and the unanimity of belief in the Real Presence (even Luther and Calvin did not dispute that unanimity – they only disputed the philosophical explanation or stressed a different aspect of it). Calvinists point to the spiritual interpretation found in many Fathers and the lack (in their view) of early mention of “transubstantiation” specifically; they also often cite the Eastern Church’s reluctance to dogmatize a mechanism (though notably Eastern Orthodoxy fully agrees with Catholicism on the result: that after consecration, it is Christ’s body and blood, period).

Conclusion

The Eucharist has been, from the earliest days, both a mystery to be revered and a doctrine to be believed. This study has traced how understanding of that mystery unfolded through four eras:

• In the Early Church (pre-150 AD), Christians already held an “unquestioningly realist” belief in Christ’s presence in the Eucharist (What the Early Church Believed: The Real Presence | Catholic Answers Tract). The Eucharist was the flesh and blood of Christ given for the life of the faithful, as attested by Scripture and the earliest Fathers. While theological terminology was rudimentary, the foundational reality of the Real Presence and the concept of a sacrificial meal were present in germ. The Catholic Church sees this period as the seed of its later doctrine, and even the Reformed tradition acknowledges the early Church’s sacramental realism, though it argues the manner was understood spiritually.

• From 150 AD to Nicaea, theologians like Justin Martyr, Irenaeus, and Tertullian expanded on Eucharistic faith. They vigorously affirmed the Eucharist’s dual nature – earthly and heavenly (ＩＲＥＮＡＥＵＳ：　”Ｎｏ　Ｌｏｎｇｅｒ　Ｃｏｍｍｏｎ　Ｂｒｅａｄ” – Ｐｈｉｌｉｐ　Ｄｅｒｒｉｄａ) – and used it to combat heresies. They maintained both the sign value (calling it a figure or antitype) and the reality (Christ’s true body and blood). The dominant view by 325 was that the Eucharist is no mere symbol but a divine mystery. This era consolidated the orthodox view that the Eucharist truly mediates Christ’s body and blood, foreshadowing the Catholic doctrine. Calvin and his followers would later reference some writers of this era (especially those who spoke of “figures”) to support the idea that the early Church did not define a change of substance – yet they could not deny that those same writers viewed the sacrament as far more than an empty symbol: it was efficacious and in some sense was Christ’s body and blood. Thus, historically, the debate is not about whether the Real Presence was believed (it clearly was), but about how it was understood.

• In the Post-Nicene and Medieval Church (325 to 1500s), Eucharistic theology reached its high refinement. The Church increasingly taught a literal, substantial presence: Saints like Ambrose and Augustine taught that the bread and wine are changed into Christ’s body and blood by consecration (Real presence of Christ in the Eucharist - Wikipedia) (Real presence of Christ in the Eucharist - Wikipedia), even if the manner is miraculous and beyond sense. Medieval scholastics coined “transubstantiation” to explain this change, and the Fourth Lateran Council (1215) dogmatically affirmed it (Real presence of Christ in the Eucharist - Wikipedia). The Eucharist’s sacrificial character was also strongly emphasized – it was understood as making present Christ’s one sacrifice, which could be offered for the living and dead. This entire vision was enshrined in late medieval Catholic devotion. Dissenters like Ratramnus or Berengar, who offered more nuanced or critical takes, were ultimately sidelined by the Church but became reference points for later Reformers. By the Reformation, the Catholic doctrine of the Eucharist was fully formed: truly Christ present (Body, Blood, Soul, Divinity) under the appearances of bread and wine, by virtue of transubstantiation, to be adored and to be offered in sacrifice in the Mass. The historical survey shows this was not a sudden medieval invention but a maturation of ideas traceable to the early Church. However, from a critical perspective, one could say certain emphases (like how exactly the sacrifice of the Mass relates to the cross, or the overuse of Aristotelian categories) were later developments that the Reformers questioned in light of the basic gospel message in Scripture.

• Reformation to Modern Times witnessed the crystallization of two distinct theological camps regarding the Eucharist. The Catholic Church, at Trent, reasserted its ancient faith in Scholastic terms (General Council of Trent: Thirteenth Session - Papal Encyclicals) and held that any denial of the substantial presence or the sacrificial nature was anathema. John Calvin, building on but modifying Luther and Zwingli, articulated a spiritual-real presence: for Calvin, the Eucharist truly gives what it signifies (Christ’s body and blood), but the mode is spiritual via the Holy Spirit and effective reception by faith (Real presence of Christ in the Eucharist - Wikipedia) (Real presence of Christ in the Eucharist - Wikipedia). This view became standard in Reformed confessions (Chapter 29.5, 6 - Reformation 21) (Chapter 29.5, 6 - Reformation 21). Over time, polemics on both sides hardened (as evidenced by confessional documents). In modern ecumenical context, there’s been greater dialogue; yet, the core differences remain. The Catholic magisterium still teaches transubstantiation and the sacrifice of the Mass; Reformed churches still reject those concepts, even if they may emphasize the mystery and avoid crude memorialist language.

Both viewpoints seek to honor Christ’s institution: Catholics by adoring the humble host as the Lord Himself and offering it in obedience to “Do this,” Calvinists by emphasizing the role of the Spirit and the necessity of faith so that the sacrament does not become a mechanical ritual. Interestingly, both can quote Augustine – one for “No one eats before worshiping” (supporting adoration) (Dominus est (English)), the other for “Believe and you have eaten” (supporting spiritual reception) (SUMMA THEOLOGIAE: The change of bread and wine into the Body and Blood of Christ (Tertia Pars, Q. 75)) (SUMMA THEOLOGIAE: The change of bread and wine into the Body and Blood of Christ (Tertia Pars, Q. 75)). Such is the richness of the tradition that the Eucharist, as Augustine also said, is a mystery of unity and charity. Tragically, it has also been a point of disunity among Christians.

From an academic historical standpoint, we conclude:

• The Catholic doctrine is deeply rooted in early and patristic Christianity and developed in continuity through the ages. Primary sources from each era (Ignatius (CHURCH FATHERS: Epistle to the Smyrnaeans (St. Ignatius)), Irenaeus (ＩＲＥＮＡＥＵＳ：　”Ｎｏ　Ｌｏｎｇｅｒ　Ｃｏｍｍｏｎ　Ｂｒｅａｄ” – Ｐｈｉｌｉｐ　Ｄｅｒｒｉｄａ), Ambrose (Real presence of Christ in the Eucharist - Wikipedia), Aquinas (SUMMA THEOLOGIAE: The change of bread and wine into the Body and Blood of Christ (Tertia Pars, Q. 75)), Trent (General Council of Trent: Thirteenth Session - Papal Encyclicals), etc.) consistently affirm a real change and identity between the Eucharistic elements and Christ’s Body and Blood. This continuity justifies the Catholic appeal to tradition and the Church’s authority to clarify doctrine (notably, no Father or council ever taught a merely symbolic view – that idea only arose with certain heretical movements or individual theologians later condemned).

• The Calvinist doctrine represents a reforming correction against what the Reformers saw as later medieval accretions. It retrieved certain patristic themes – especially the need for faith and the spiritual interpretation – and opposed what it considered unscriptural definitions. Calvin’s view can claim support from some strands in Augustine, Ratramnus, and others, though it stands in clear opposition to the medieval consensus. It is a theologically coherent alternative that seeks to safeguard the transcendence of Christ’s glorified body and the primacy of faith. For instance, Calvin feared that transubstantiation leads people to adore the elements rather than Christ Himself (he thought many uneducated Catholics viewed the bread as a sort of magic object, which to him was idolatry). The Reformed stress on the Spirit and Word ensures the Supper is seen as God’s action through promise, not a quasi-automatic miracle at a priest’s command.

In the end, the Eucharist remains, in the words of the Second Vatican Council, “the source and summit of the Christian life” for Catholics, and for Reformed Christians, it is a vital “means of grace” and a visible Word that nourishes believers. Despite doctrinal differences, both traditions deeply value the sacrament: one in the mystery of transubstantiated presence, the other in the power of spiritual communion. The historical journey of Eucharistic theology thus reflects the broader Christian journey – a continual attempt to fathom the unfathomable gift that Christ left us. As a mystery of faith, the Eucharist ultimately eludes full human understanding. It beckons Christians to unity at one table, even as interpretations of it have sadly divided them. Perhaps an objective scholarly appreciation of the rich historical tapestry – as we have attempted above – can foster greater mutual respect. Both views, in their own logic, aim to be faithful to Christ’s words, “Take, eat; this is my body… Drink of it; this is my blood… given for you… Do this in remembrance of me.” Whether one encounters Christ substantially present in the Host or spiritually present in the act of Communion, the believer is drawn to the same reality: Jesus Christ, crucified and risen, giving Himself to His people for the forgiveness of sins and eternal life. In that sense, the Eucharist in all historic Christian traditions remains what Ignatius of Antioch in 107 AD called it: “the medicine of immortality, the antidote against death, enabling us to live forever in Jesus Christ”.

Sources:

• Holy Scripture (e.g. Luke 22:19-20; 1 Cor 10:16-17, 11:23-29; John 6:52-58).
• Didache, c. 1st cent., chapters 9-10 (early Eucharistic prayers).
• Ignatius of Antioch, Letter to the Smyrnaeans 6–7 (c. 107 AD): “They abstain from the Eucharist… because they confess not the Eucharist to be the flesh of our Saviour Jesus Christ” (CHURCH FATHERS: Epistle to the Smyrnaeans (St. Ignatius)). Also Letter to the Romans 7 (Views on the Eucharist - 110 AD | TexAgs).
• Justin Martyr, First Apology ch. 66 (c. 155): description of Eucharist as “not common bread… the food blessed by the prayer of His word is the flesh and blood of that Jesus who was made flesh” (CHURCH FATHERS: The First Apology (St. Justin Martyr)).
• Irenaeus, Against Heresies IV.18.5 & V.2.2 (c. 180): “the bread… receiving the invocation of God, is no longer common bread but the Eucharist, consisting of two realities, earthly and heavenly” (ＩＲＥＮＡＥＵＳ：　”Ｎｏ　Ｌｏｎｇｅｒ　Ｃｏｍｍｏｎ　Ｂｒｅａｄ” – Ｐｈｉｌｉｐ　Ｄｅｒｒｉｄａ); “He declared the bread, a part of creation, to be His body” (What the Early Church Believed: The Real Presence | Catholic Answers Tract).
• Tertullian, Against Marcion IV.40 (c. 210): “‘This is My body,’ i.e., the figure of My body.” (Real presence of Christ in the Eucharist - Wikipedia). And De Corona 3: “We take in the sacrament of the Eucharist… the flesh of Jesus Christ”.
• Origen, Contra Celsum 8.57 (c. 248): “We have a symbol of gratitude to God in the bread which we call the Eucharist.” (Origen - Against Celsus - Book VIII - Search Early Christian Writings).
• Cyril of Jerusalem, Mystagogical Catechesis 4 (c. 350): “Do not regard the bread and wine as simply that… for they are, according to the Master’s declaration, the body and blood of Christ.”
• Ambrose of Milan, On the Mysteries 9.50-52 (c. 390): “Before consecration it is bread… After consecration, it is the Body of Christ… by the words of Christ, the nature is changed.” (Real presence of Christ in the Eucharist - Wikipedia) (Real presence of Christ in the Eucharist - Wikipedia).
• Augustine of Hippo: Sermon 272: “That bread which you see on the altar, having been sanctified by the word of God, is the Body of Christ… What your eyes see is the bread and the chalice; but what your faith obliges you to accept is that the bread is the Body of Christ, the chalice the Blood of Christ.”; Enarration on Psalm 98 (c. 400): “No one eats that flesh unless he first adores… we do not sin by adoring” (Dominus est (English)); Tractates on John 25: “Understand spiritually what I have said. You are not to eat this body which you see, nor to drink the blood which those who crucify me will spill… Believe, and you have eaten.” (SUMMA THEOLOGIAE: The change of bread and wine into the Body and Blood of Christ (Tertia Pars, Q. 75)) (SUMMA THEOLOGIAE: The change of bread and wine into the Body and Blood of Christ (Tertia Pars, Q. 75)).
• Council of Ephesus (431) referred to the “sacrifices” offered in churches, indicating belief in Eucharistic sacrifice.
• Paschasius Radbertus, De Corpore et Sanguine Domini (831): taught identity of sacramental and historical Body of Christ.
• Ratramnus of Corbie, De Corpore et Sanguine Domini (c. 833): “the faithful receive the body of Christ in a mystery, not in a literal truth… the substance of bread and wine remain, but they are figures of the true body and blood” (Real presence of Christ in the Eucharist - Wikipedia) (Real presence of Christ in the Eucharist - Wikipedia).
• Berengar of Tours (1079 confession): “I, Berengarius, believe… the bread and wine… are changed into the true and proper and life-giving flesh and blood of Jesus Christ… and that after consecration there is present the true Body of Christ which was born of the Virgin and hung on the Cross”.
• Fourth Lateran Council (1215), Canon 1: “…the sacrament of the altar… in which the bread is transubstantiated into the Body [of Christ] and the wine into the Blood…” (Real presence of Christ in the Eucharist - Wikipedia).
• St. Thomas Aquinas, Summa Theologiae III, Q.75 a.1: “Christ’s true body and blood are present in this sacrament… not perceptible by sense, but by faith alone, which rests on divine authority.”【50†L1-L4}; Q.75 a.4: “If anyone says that the substance of bread and wine remain after consecration… let him be anathema” (Aquinas cites the Church’s authority and calls opposing view heretical) (SUMMA THEOLOGIAE: The change of bread and wine into the Body and Blood of Christ (Tertia Pars, Q. 75)).
• Martin Luther, The Babylonian Captivity of the Church (1520): “It is not necessary to assert that transubstantiation occurs… It is sufficient to say that Christ’s body and blood are truly present…”; “Since it is not necessary to assume transubstantiation wrought by divine power, it is to be regarded as a figment of the mind, having no basis in Scripture or reason” (A Prelude on the Babylonian Captivity of the Church (1520)). He also wrote: “The only essential thing is that Christ’s body is present; how it comes there is secondary”.
• John Calvin, Institutes of the Christian Religion (1559) IV.17: “We confess that in the Lord’s Supper Christ Jesus offers us His body and blood truly, to be our spiritual food. The power of the Holy Spirit is the bond of this participation. Distance is no obstacle: the Spirit truly unites things separated in space (Real presence of Christ in the Eucharist - Wikipedia). The flesh and blood of Christ are truly given to unbelievers as well as believers, but only believers receive them to life; unbelievers receive no benefit (Real presence of Christ in the Eucharist - Wikipedia). The presence is not carnal, but spiritual – that is, by the Spirit’s agency.” (Paraphrase synthesizing Calvin’s remarks). Also “This mystery of Christ’s presence is so sublime that I cannot comprehend it with my mind… nor do I desire to measure its sublimity with my reason. I exhort the reader to not confine his belief within narrow limits, but rather to strive to rise much higher than I can guide him” (Kovacs_Gergo-The Reformed-Roman Catholic dialogue on the eucharist_mas062012).
• Council of Trent, Session 13, Decree on the Eucharist (1551): “In the blessed sacrament of the Holy Eucharist, after the consecration of the bread and wine, our Lord Jesus Christ, true God and man, is truly, really, and substantially contained under the appearance of those sensible things… By the consecration of bread and wine, a conversion is made of the whole substance of bread into the substance of the Body of Christ, and of the whole substance of wine into the substance of His Blood; this conversion is called Transubstantiation by the Holy Catholic Church.” (General Council of Trent: Thirteenth Session - Papal Encyclicals) Trent also anathematizes those who deny this or who say Christ is present only in a sign or figure (General Council of Trent: Thirteenth Session - Papal Encyclicals).
• Westminster Confession of Faith (1646), ch. 29: “In this sacrament, Christ is not offered up to His Father, nor any real sacrifice made at all… The Lord’s Supper is only a memorial of that one offering, and a spiritual oblation of praise. … The outward elements of bread and wine, set apart by Christ’s words, remain truly and only bread and wine in substance, but are so related to Christ crucified that they are sometimes called by the name of the things they represent, namely, the Body and Blood of Christ (Chapter 29.5, 6 - Reformation 21). … The Body and Blood of Christ are not corporally or carnally present in, with, or under the bread and wine, but spiritually present to the faith of believers” (Chapter 29.5, 6 - Reformation 21) (Chapter 29.5, 6 - Reformation 21). And it condemns transubstantiation as “repugnant to Scripture and reason” (Chapter 29.5, 6 - Reformation 21).
• Catechism of the Catholic Church (1992), §§1373-1381: reaffirms Trent using modern language (e.g., “Christ is present in many ways to His Church… but He is present most especially in the Eucharistic species”; “the mode of Christ’s presence in the Eucharist is unique; in the sacrament of the Eucharist the bread and wine become the Body and Blood of Christ… a change which the Church calls transubstantiation” (Here is what St. Irenaeus said about the Eucharist) (Here is what St. Irenaeus said about the Eucharist); “it is by the conversion of the bread and wine into Christ’s Body and Blood that Christ becomes present… This presence begins at the moment of consecration and endures as long as the species subsist”). It also quotes St. Thomas: “That in this sacrament are the true Body of Christ and His true Blood is something that cannot be apprehended by the senses, but only by faith, which relies on divine authority” (SUMMA THEOLOGIAE: The change of bread and wine into the Body and Blood of Christ (Tertia Pars, Q. 75)).

These sources, spanning two millennia, underpin the analysis in each section above. By examining them, we see the continuous thread of Eucharistic belief and the points at which interpretations diverged. The Eucharist, as an academic subject, thus offers a fascinating case study in doctrinal development, scriptural exegesis, and the interplay of faith and reason in Christian theology. The comparative study of the Catholic and Calvinist views, grounded in primary sources, not only illuminates their differences but also highlights a shared reverence for the Sacrament – a reverence that ultimately stems from Christ’s own command and promise: “Take and eat… take and drink… Do this in remembrance of me.”

(CHURCH FATHERS: Epistle to the Smyrnaeans (St. Ignatius)) (CHURCH FATHERS: The First Apology (St. Justin Martyr)) (ＩＲＥＮＡＥＵＳ：　”Ｎｏ　Ｌｏｎｇｅｒ　Ｃｏｍｍｏｎ　Ｂｒｅａｄ” – Ｐｈｉｌｉｐ　Ｄｅｒｒｉｄａ) (Real presence of Christ in the Eucharist - Wikipedia) (A Prelude on the Babylonian Captivity of the Church (1520)) (Real presence of Christ in the Eucharist - Wikipedia)