Chapter 39: Transubstantiation

Transubstantiation [900] is the change of the whole substance of bread into the body of Christ and of the whole substance of wine into the blood of Christ. This truth is indispensable in explaining the Real Presence. If the glorious and impassible body of Christ does not cease to be in heaven, it cannot become present under the species of the bread and the wine by an adductive action which would make that body descend from heaven to each host consecrated. Hence, if the body of Christ Himself is not subject of the change, He cannot become really present except by the change into Him of the substances of bread and wine. Briefly, if a body becomes present there where before it was not, then, by the principle of identity, this body must undergo a change of place, or then another body must be changed into it. To illustrate. A pillar, remaining immovable, which was at my right, cannot be at my left unless I have changed in my relation to it. Again: If in a house where there was no fire we now find a fire, that fire either must have been brought there or produced there. [901].

By this change, then, of the substance of the bread into the body of Christ, this body, itself remaining unchanged, becomes really present under the accidents of the bread, because these accidents lose the real and containing relation they had to the substance of the bread and they acquire a new, real, and containing relation to the body of Christ. This new real relation presupposes a real foundation, which is transubstantiation.

This position granted, St. Thomas draws therefrom all other Eucharistic truths, particularly in regard to the Real Presence, and the Eucharistic accidents. He is faithful to the principle of economy which tells us to explain facts without useless multiplication of causes.

This doctrine of St. Thomas is not admitted by Scotus, who explains the Real Presence by annihilation of the substance of the bread and adduction of the substance of Christ's body. [902] Many other theologians, [903] following him in part, speak of an "adductive transubstantiation." Speaking thus, they no longer preserve the proper meaning of the words "conversion" and "transubstantiation," words used in conciliar decrees. To speak of transubstantiation as adductive is to deny the conversion of one substance into another, and to affirm the substitution of one for the other.

Further, what is the meaning of "adduction," if Christ's impassible body remains in heaven? Christ's body, Thomists repeat St. Thomas, does not become present by any change in itself, local, quantitative, qualitative, or substantial. Hence the real presence of that body has no other explanation than the substantial change of the bread into that body.

But can we, with Suarez, say that transubstantiation is quasi-reproductive of Christ's body? No, because that body is in heaven as it was before, neither multiplied nor changed. It is numerically the same glorified body which is in heaven and in the Eucharist. Gonet and Billuart, who indulge somewhat in the terminology of Suarez, nevertheless teach, like other Thomists, that transubstantiation is a substantial change in the proper sense of the word. "Thus it comes," says the Catechism of the Council of Trent, [904] "that the entire substance of the bread is by divine power changed into the entire substance of Christ's body without any mutation in our Lord."

Which view is verified in the sacramental formula: This is My body? This formula most certainly expresses neither annihilation nor adduction, whereas, by being causatively true, it does express conversion of the entire substance of the bread into the substance of Christ's body. Besides, annihilation does not include adduction, nor the inverse. And the Council of Trent [905] speaks not of two divine interventions, distinct and independent, but of one intervention only, by which the entire substance of the bread is changed into Christ's body, and the entire substance of the wine is changed into Christ's blood. And this change, the Council adds, is rightly called transubstantiation.

In what precisely does transubstantiation terminate? Cajetan, [906] followed by Thomists generally, gives answer by this formula: That which was bread is now Christ's body, not Christ's body taken absolutely, as it existed before transubstantiation, but Christ's body as terminus of this transubstantiated bread. [907] More explicitly, transubstantiation terminates in this, that what was the substance of bread is now the body of Christ.

Is transubstantiation an instantaneous process? Yes, one and the same indivisible instant terminates the existence of the bread [908] and initiates Christ's existence under the species of bread. [909].

How is transubstantiation possible? St. Thomas [910] has recourse to the Creator's immediate power over created being as being. If God can produce the whole creation from nothing, He can also change the entity of one thing into that of another. Whereas in a substantial mutation there is a subject (prime matter) which remains under the two successive forms, here in transubstantiation there is no permanent subject, but the whole substance of bread, matter and form, is changed into that of Christ's body. [911] These formulas reappear in the Council of Trent. [912].

Let us note some consequences of this doctrine. Christ's body is in the Eucharist, not as in a place but in the manner of substance. [913] The quantity of Christ's body is also really present in the Eucharist, but again, in the manner of substance, that is, by its relation, not to place, but to its own substance, since it is present, not by local adduction, but only by a change exclusively substantial. Thus we see too that it is numerically the same body which, without division or distance, is simultaneously in heaven and in the Eucharist, because it is present in the Eucharist illocally, in the manner of substance, in an order superior to the order of space.

By this same line of reasoning St. Thomas [914] explains the Eucharistic accidents, as existing without any subject of inhesion. All other Eucharistic theses are simply corollaries from his teaching on transubstantiation. The principle of economy could not be better exemplified. We cannot say the same of the theories which have been substituted for that of St. Thomas. They are complicated, factitious, useless. They proceed by a quasi-mechanical juxtaposition of arguments, instead of having an organic unity, which presupposes as source one mother-idea. Here again we see the wonderful power of the Thomistic synthesis.