The Eucharist: Liturgy of the Eastern Churches and Their Theological Implication

This paper explores the theological and liturgical distinctions between the Eastern Orthodox, Oriental Orthodox, and Western Christian traditions regarding the Eucharist, particularly focusing on the type of bread used and the role of the Holy Spirit in the transformation of the Eucharistic elements. A significant difference is found in the use of leavened versus unleavened bread, which has theological implications related to the representation of Christ’s crucifixion and resurrection. In the Roman Rite of the Catholic Church, the use of unleavened bread reflects Christ’s Passover sacrifice and his death, whereas in the Eastern Orthodox tradition, leavened bread symbolizes the resurrection, as its rising mirrors Christ’s triumph over death. This distinction is rooted in broader theological differences, particularly concerning soteriology. While Western Christian traditions emphasize Christ’s crucifixion and its atoning role in response to the doctrine of Original Sin—an Augustinian concept formally articulated in councils such as Carthage (418 CE), Orange (529 CE), and Trent (1545–1563 CE)—the Eastern Churches reject the notion of inherited guilt from Adam. Instead, they uphold the concept of Ancestral Sin, which posits that humanity has inherited Adam’s tendency to sin and mortality but not his culpability. The Eastern theological framework thus focuses on the reconciliation of humanity through Christ’s resurrection, which restores creation from the corruption of death.

The preference for leavened bread in the Eastern Churches, with the exception of the Armenian tradition, reflects this theological emphasis. Historical evidence suggests that early patristic writings were largely silent on the type of bread used in the Eucharist, indicating that this was not a primary concern in early Christian communities. Unlike the extensive discussions on the necessity of mixing wine with water in the Eucharist, there is little early Christian debate regarding the nature of the bread. The first explicit condemnation of unleavened bread appears in Canon 11 of the Quinisext Council (692 CE), which sought to differentiate Christian practice from Jewish customs, an effort that can be traced back to Canon 70 of the Apostolic Canons (5th–6th centuries). While the Quinisext Council’s decisions were accepted by the Byzantine Church, they were met with opposition in the Roman Church, though at that time, the debate did not yet center on the use of unleavened bread. Notably, even within the Roman Catholic Church, leavened bread has not been categorically disallowed, as some Eastern Catholic rites continue its use in the Eucharist.

Beyond the question of bread, another key distinction between the Eastern and Western Churches pertains to the moment at which the transformation of the Eucharistic elements is believed to occur. In the Roman Catholic tradition, the bread and wine are considered to become the body and blood of Christ at the moment of consecration, when the priest pronounces the words of institution. In contrast, the Eastern Churches do not pinpoint an exact moment of transformation but rather emphasize the entire anaphora as a sacred mystery culminating in the epiclesis, the invocation of the Holy Spirit. This reflects a broader theological difference regarding the role of the Spirit in the Eucharist. The Eastern tradition views the Holy Spirit as working throughout the liturgical celebration, in contrast to the more defined moment of consecration in the Western tradition.

This distinction in Eucharistic theology may also relate to the differing interpretations of the Last Supper. The Synoptic Gospels present the Last Supper as a Passover meal, explicitly stated in Luke 22:15, implying that Christ and his disciples would have used unleavened bread. However, the Gospel of John situates the Last Supper a day before Passover, emphasizing Christ’s role as the sacrificial Lamb of God on the day of his crucifixion. If the Eastern Churches give theological primacy to the Johannine narrative, then the Last Supper would not have been a Passover meal, meaning that leavened bread may have been used. This aligns with the Eastern theological emphasis on the Holy Spirit, which is central to the Johannine Farewell Discourse, where Christ promises the coming of the Spirit. If the Johannine framework is given precedence, it reinforces the preference for leavened bread and supports a Eucharistic theology that focuses on the resurrection rather than the crucifixion.

By examining these theological and liturgical differences, this paper seeks to provide a deeper understanding of how variations in Eucharistic practice reflect broader doctrinal distinctions between the Eastern and Western Christian traditions. The divergence in the use of leavened versus unleavened bread, as well as differences in the role of the Holy Spirit in the Eucharist, are not merely ritualistic variations but are deeply tied to each tradition’s soteriology and understanding of Christ’s redemptive work. Recognizing these differences sheds light on the historical development of Christian theology and offers a richer perspective on the complexities of Eucharistic doctrine across the Christian world.