Here in Rome, Italy, near the heart of Roman Catholicism, it is not unusual to pass by one of the city’s countless Catholic churches and see people prostrate on the floor or on bended knee as the priest carries around the bread of the Eucharist.

This is a pinnacle moment in the life of Catholics. They claim to be worshiping the actual body and actual blood of Christ, which have taken over the elements of the bread. As The Catechism of the Catholic Church (CCC) reads,

In the liturgy of the Mass we express our faith in the real presence of Christ under the species of bread and wine by . . . genuflecting or bowing deeply as a sign of adoration of the Lord. The Catholic Church has always offered and still offers to the sacrament of the Eucharist the cult of adoration. (CCC, 1378)

In the Eucharist, they believe, Christ’s sacrificial work on the cross is made present, perpetuated, and reenacted. This understanding of the Eucharist depends on the Catholic Church’s teaching of transubstantiation, which has a central place in the Catholic faith.

What Is Transubstantiation?

The Catholic Church teaches that during the Eucharist, the body of Jesus Christ himself is truly eaten and his blood truly drunk. The bread becomes his actual body, and the wine his actual blood. The process of this change is called transubstantiation:

By the consecration of the bread and wine there takes place a change of the whole substance of the bread into the substance of the body of Christ our Lord and of the whole substance of the wine into the substance of his blood. This change the holy Catholic Church has fittingly and properly called transubstantiation. (CCC, 1376)

To explain this phenomenon, Catholic theology presses Aristotelian philosophy into service. A distinction is made between substance and accidents. The substance of a thing is what that thing actually is, while accidents refer to incidental features that may have a certain appearance but can be withdrawn without altering the substance.

During the Eucharist, then, the substance of the bread and wine are changed into the body and blood of Christ, while the accidents remain the same. The bread and wine actually become the body and blood of Christ, it is claimed, but maintain the appearance, texture, smell, and taste of bread and wine. The Catholic Church does not claim that this is a magical transformation, but that it is instead a sacramental mystery that is administered by those who have received the sacrament of order.

Where Did Transubstantiation Come From?

Like many aspects of Roman Catholic theology and practice, it is difficult to point to one definitive person or event to explain how transubstantiation entered into Catholic Church. It was more of a gradual development that then reached a decisive moment at the Fourth Lateran Council in 1215, where the teaching and belief were officially affirmed. However, by the second century, the view that the bread and wine are in some unspecified way the actual body and blood of Jesus had already surfaced. This is evidenced, for example, in the writings of Ignatius of Antioch (died around AD 108) and Justin Martyr (died AD 165), though their references to the nature of the Eucharist are somewhat ambiguous.

It is also true, however, that the early church fathers were countering certain gnostic teachings that claimed that Jesus never had a real human body but was only divine in nature. It was not possible, said the critics, that his body was present during the Eucharist. In response, some early church fathers insisted on the real presence of Christ’s body and blood in the sacrament. Moreover, both Origen (185–254) and Cyprian (200–258) spoke of the sacrament as a eucharistic sacrifice, thus unhelpfully introducing sacrificial language into the Lord’s Supper. Ambrose of Milan (died 397) understood the Eucharist in these sacrificial terms, as did John Chrysostom (died 407). Jesus’s words in John 6:53–56 appeared to provide the biblical framework they needed to make their argument: “Truly, truly, I say to you, unless you eat the flesh of the Son of Man and drink his blood, you have no life in you” (John 6:53).

Over the centuries, this belief developed until it eventually became official church dogma. It would not be without its challengers, however. Ratramnus (ninth century) and Berengarius (eleventh century) are notable examples of those who did not accept the claim that the substance of the bread and wine change in the Supper.

“To say that transubstantiation teaches that God is eaten is not an exaggeration or a misrepresentation.”

Transubstantiation would receive its greatest challenge in the sixteenth century from the Protestant Reformation. During the Council of Trent (1545–1563), which was the Catholic response to the Protestant Reformation, the Roman Catholic Church renewed with great enthusiasm its commitment to the doctrine, and thus to the conviction that during the Eucharist, God incarnate is indeed eaten. Matteo Al-Kalak — a professor of modern history at the University of Modena-Reggio in Italy — affirms that this concept is still fully embraced in a recent book titled Mangiare Dio: Una storia dell’eucarestia — Eating God: A History of the Eucharist. To say that transubstantiation teaches that God is eaten is not, then, an exaggeration or a misrepresentation.

His Sacrifice Cannot Be Repeated

The Protestant Reformation rightly rejected the Roman Catholic doctrine of transubstantiation. In the Old Testament, the priests entered the tabernacle repeatedly in order to offer blood sacrifices for the sins of God’s people. Christ, however, by means of his death and resurrection, entered into heaven and mediates on our behalf once and for all (Hebrews 7:27). His is not a sacrifice that needs to be or even can be repeated (Hebrews 9:11–28). It is sufficient. It is final (John 19:30). If, however, the bread and wine of the Eucharist indeed undergo a change of substance and become the real body and blood of Christ, Christ’s sacrifice on the cross is neither sufficient nor final; instead, it is continually re-presented and made present. Thus, transubstantiation undermines the clear teachings of Scripture.

“Christ’s is not a sacrifice that needs to be or even can be repeated. It is sufficient. It is final.”

In response, Martin Luther (1483–1546) proposed a somewhat confused alternative with his doctrine of what came to be called consubstantiation. He taught that Christ’s body and blood are substantially present alongside the bread and wine. This was different from transubstantiation in that there was no change in the substance of the bread and wine itself. Luther’s theory, however, was susceptible to similar objections to those of transubstantiation. Huldrych Zwingli (1484–1531), another Reformer and contemporary of Luther, promoted the idea that the Lord’s Supper is symbolic and is solely a memorial of Christ’s work on the cross. Zwingli’s view is widely accepted in many evangelical circles today.

Transubstantiation receives its most helpful answer and alternative, however, in the classic Reformed view of the Lord’s Supper, deriving from John Calvin (1509–1564). The Reformed view promotes the understanding that while there is no change of substance in the sacrament, Jesus Christ is nonetheless present in a real way by means of his Holy Spirit. In observing the Lord’s Supper, Christ does not come down to the faithful in his body and blood; instead, the faithful are lifted up to him in spirit by the Holy Spirit.

As truly as the faithful eat in faith the bread and drink the wine, so they spiritually feed on Christ. The physical and spiritual are not merged, as they are in transubstantiation, nor are they completely separated. Instead, they are distinct but at the same time, through the ministry of the Spirit and the exercise of genuine faith, inseparable.