St. Gregory of Nyssa’s Amazing Explanation for the Eucharist

If the truth of the Eucharist has ever seemed strange to you, that’s because it should.

St. Paul said, “We preach Christ crucified, to the Jews indeed a stumbling block, and to the Gentiles foolishness.” The Eucharist is the enduring testament to the reality of the crucifixion of God Incarnate. So it is fitting that the Eucharist is its own stumbling block for some. That bread and wine could be turned into the body and blood and soul and divinity of Christ is certainly foolishness to our hyper-empiricist world.

At the same time, as believers our faith in this mystery is one that also seeks to understand it. To be sure,  St. Thomas Aquinas carves out a small intellectual foothold in his doctrine of transubstantiation, which helps us to grasp the raw mechanics of how the Eucharist is transformed.

But many of us yearn for a deeper understanding. Enter St. Gregory of Nyssa.

In his Great Catechism, this early Church Father offers a threefold explanation that illuminates the why, the how, and the what of the Eucharist.

Why the Eucharist

Let’s take a step back for a moment. Why the Eucharist in the first place? Why did God ordain this as the summit of the sacraments to which we must ascend again and again on our journey to Him? Why food?

The question gains force when we contrast it with the other sacraments. In baptism, we can readily see the analogy between physical washing and the cleansing of our sins. In marriage, the joining together of man and woman is an obvious metaphor for the union of man with God. But food? The implications are less obvious. True, we require daily bread for our physical nourishment, but why do we need it for spiritual sustenance?

In the Great Catechism, Gregory says the answer lies in Eden:

[T]hey who owing to some act of treachery have taken poison, allay its deadly influence by means of some other drug—for it is necessary that the antidote should enter the human vitals in the same way as the deadly poison, in order to secure, through them, that the effect of the remedy may be distributed through the entire system (Great Catechism, 37).

In other words, just as sin was introduced to mankind through the act of eating, it is necessary that the antidote enter the body in the same manner. There is a certain self-evident symmetry to the argument here. It is also consistent with God’s whole plan of redemption, in which God undid the first sin and its consequences through a new Adam and a new Eve, Christ and Mary. The whole gospel story, in a sense, is a redemptive reenactment of Eden, from the announcement of the angel to Mary to Christ’s death on a tree.

Gregory also elaborates on how the antidote of the Eucharist works, drawing on a chemical analogy. The forbidden fruit, he said, dissolved our nature. Though he does not develop his point further, traditional teaching discerns three ways this happened: First, the disorder was introduced in human nature, in which the soul was ruled by the body rather than the other way around. Due to original sin, this eventually ends in death, which is defined as the separation of the body and soul. Second, there is disorder in our relationships with each other. And third, there is our separation from God.

The Eucharist, as Gregory says, is the ultimate combination agent. It unites us with Christ, who is God-made-man. In so doing it restores the order between body and soul leading to eternal life, instead of death. It also binds fellow partakers into one mystical Body of Christ.

How the Eucharist works

But how can the Eucharist do this? How is the Eucharist actually an antidote?

According to Gregory, the natural source of the remedy for the poison is that body which has shown itself ‘immune’ to the effects of sin and death. As he puts it, “What, then, is this remedy to be? Nothing else than that very Body which has been shown to be superior to death, and has been the First-fruits of our life.”

Christ showed Himself ultimately able to overcome death and sin by His self-offering on the cross and His resurrection. On this point, Gregory anticipates one technique modern medicine uses to treat disease — transferring antibodies from someone with immunity to someone who lacks those antibodies. (Here is a further explanation.)

Given Gregory’s emphasis on the body and the pervasive lasting effects of the sin, we anticipated that some people might wonder how the Eucharist can be so powerful. This isn’t to question the power of God. Rather it’s to ask how a small piece of bread and a sip of wine can be effective vehicles of that power.

To answer this, Gregory turns to another analogy: that of leaven. Just as a small amount of yeast can leaven a whole loaf of bread, so also the Eucharist can inflate us out of a state of spiritual flatness. If yeast can do that to bread, just think what transubstantiated bread and wine could do to us.

What is the Eucharist?

Thus far, Gregory of Nyssa has explained the why and how of the Eucharist: why we need it and how it operates. But our pious curiosity centers over the what of the Eucharist—what it is, which, Scripture, tradition, and the Church teach us is the Real Presence of Christ.

Gregory begins by reframing this as a question of how: How can the bread and wine be Christ? Gregory of Nyssa responds by saying that the bread is a kind of prototypical food, just as wine was, in the ancient world, a fundamental source of fluids for all men. And, because of this characteristic bread and wine are a type of the human body. As he puts it:

Some animals feed on roots which they dig up. Of others grass is the food, of others different kinds of flesh, but for man above all things bread; and, in order to continue and preserve the moisture of his body, drink, not simply water, but water frequently sweetened with wine, to join forces with our internal heat. He, therefore, who thinks of these things, thinks by implication of the particular bulk of our body. For those things by being within me became my blood and flesh, the corresponding nutriment by its power of adaptation being changed into the form of my body (Great Catechism, 37).

Actually, all Gregory has done here is address how the Eucharistic bread and wine can represent the body and blood of Christ. This is a helpful answer in so far as it is a necessary step towards understanding how the bread and wine could be God Incarnate. Now he turns to this second question:

[W]hen He came in a body such as ours did not innovate on man’s physical constitution so as to make it other than it was, but secured continuance for His own body by the customary and proper means, and controlled its subsistence by meat and drink (Great Catechism, 37).

Put simply, the Eucharist can be the body and blood, soul and divinity of Christ because that’s similar to what happened on a daily basis during Christ’s life on earth: all the food and drink He consumed became part of His Sacred body, just as food and drink does for us. To build on Gregory’s point, this process is intensified in the Eucharist, in which bread and wine are not only transformed into the body and blood of Christ, but also into His soul and divinity. Gregory concludes,

For that Body was once, by implication, bread, but has been consecrated by the inhabitation of the Word that tabernacled in the flesh. Therefore, from the same cause as that by which the bread that was transformed in that Body was changed to a Divine potency, a similar result takes place now. For as in that case, too, the grace of the Word used to make holy the Body, the substance of which came of the bread, and in a manner was itself bread, so also in this case the bread (Great Catechism, 37).

In effect, Gregory is saying that Christ is transforming the Eucharist into Himself in much the same way that He absorbed food and drink into His body during His earthly life.

But Gregory has given us a basis for going one step further than this: in eating the Eucharist bread and wine, we are re-enacting Christ’s own Incarnate existence on this earth. This is a great truth to ponder. Consider for a moment its core meaning: Christ so ardently desires that we be transformed into Him that He ordains a special way that we can participate in His own way-of-being on a deeply personal and intimate level. It is something for which we can draw up analogies yet it is also vastly dissimilar than anything else we can experience in this life.

Ultimately, then, our quest to understand the Eucharist has not robbed it of its dazzling strangeness. Rather it has opened our eyes yet further to the blinding radiance of this great mystery.

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Stephen Beale is a freelance writer based in Providence, Rhode Island. Raised as an evangelical Protestant, he is a convert to Catholicism. He is a former news editor at and was a correspondent for the New Hampshire Union Leader, where he covered the 2008 presidential primary. He has appeared on Fox News, C-SPAN and the Today Show and his writing has been published in the Washington Times, Providence Journal, the National Catholic Register and on and A native of Topsfield, Massachusetts, he graduated from Brown University in 2004 with a degree in classics and history. His areas of interest include Eastern Christianity, Marian and Eucharistic theology, medieval history, and the saints. He welcomes tips, suggestions, and any other feedback at bealenews at gmail dot com. Follow him on Twitter at

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