Transubstantiation and the Eucharist

By: David Armstrong March 16, 2010 3 Comments

Both “transubstantiation” and “Eucharist” are big words foreign to the everyday language of everyday Americans. We may be more familiar with words like “Monosodium glutamate,” “euthanasia” or “inalienable rights,” but yet in the same sense even these terms can make us feel intellectually lethargic.

I suppose most people mentally run by and assume the meaning of these terms much like most people drive and depend on automobiles which they haven’t the foggiest idea how they actually run, let alone how to fix them. But when they do break down, or when foods with MSG start giving you headaches, it’s time to start understanding these things we’ve taken for granted.

When it comes to the Eucharist—or the Lord’s Supper as it is called by most Christian groups—and what really happens when the minister proclaims the words of consecration, there are many presumptions and misunderstandings floating around, especially when one Christian group tries to explain what another group believes. Too often, people who don’t sit well with big words pass off their own opinions as fact to unsuspecting disciples. This has been particularly true in an increasing way over the last 500 years. What Catholics believe by these two terms—transubstantiation and Eucharist—is misunderstood by not only many outside the Catholic Church but also by many within it.

On October 11, 1551, the Council of Trent, in its Decree Concerning the Most Holy Sacrament of the Eucharist (the Greek word for “thanksgiving”), defined the following propositions—which had always been the prevailing beliefs throughout Church history—as absolutely binding on all Catholics:

In the august 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 species of those sensible things. (1)

Immediately after the consecration the Veritable Body of our Lord and His veritable Blood, together with His soul and divinity, are under the species of bread and wine . . . as much is contained under either species as under both. (2)

By the consecration of the bread and of the wine a conversion is made 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; which conversion is by the holy Catholic Church suitably and properly called transubstantiation. (3)

When the Catholics Church teaches that Christ is substantially and physically presence in the Eucharist, this doesn’t negate other types of Christ’s spiritual presence. Rather, this is referred to as “real” because it is a presence in the fullest possible sense of the word. (4) Therefore, the Catholic understanding of the Real Presence of the body and blood of Christ in the Eucharist must by its very nature be distinguished from God’s omnipresence, or a merely symbolic, “spiritual” presence. The great German Catholic theologian Karl Adam lucidly described the Eucharist:

So completely does Jesus disclose Himself to His disciples . . . that He gives Himself to them and enters into them as a personal source of grace. Jesus shares with His disciples His most intimate possession, the most precious thing that He Has, His own self . . . So greatly does Jesus love His Community, that He permeates it . . . with His real Self, God and Man. He enters into a real union of flesh and blood with it, and binds it to His being even as the branch is bound to the vine. (5)

The Catholic Church teaches that there are many purposes of the Eucharist, and numerous spiritual benefits which accrue from partaking in Communion at Mass—provided this is undertaken in a “worthy manner” and without conscious mortal sin. (6) It is the “source and summit of the Christian life,” (7) the sign of Christian unity, (8) and of the Body of Christ, the Church, (9) an act of Thanksgiving to God, (10) a memorial and sacrifice, (11) the central focus of the liturgy and Mass, (12) the empowering of the faithful for ministry, (13) a symbol of God’s faithfulness and miraculous provision, (14) an anticipation of the wedding feast of the Lamb in heaven, (15) a remembrance of the Last Supper, (16) and of Christ’s Passion, Resurrection, and return, (17) a sign of salvation, the “bread of heaven,” (18) adoration and worship of God, (19) union with Christ, (20) the means of grace, cleansing from sin, and spiritual renewal, (21) and an offering for the dead. (22)

The daunting word “transubstantiation” is easily understood when broken down: “trans” means “change.” Therefore, the term is defined literally as the process of change of substance. The Catholic Church, in seeking to understand the true presence of Christ in the Eucharist, a doctrine delivered directly by our Lord and St. Paul, gradually developed an explanation as to the exact nature of this miraculous and mysterious transformation.

Contrary to the common misconception, transubstantiation is not dependent upon Aristotelian philosophy, since some notion of the concept goes back to the earliest days of the Church when Aristotle’s philosophy was not known. The eastern Fathers, before the sixth century, used the Greek expression metaousiosis, or “change of being,” which is essentially the same idea. The Church did, however, draw upon prevalent philosophical categories, such as substance and accidents. In all ages, Christians have sought to defend Christianity by means of philosophy and human learning (wherever the individual intellectual categories utilized were consistent with Christian faith). St. Paul, for instance, did this in his sermon on Mars Hill in Athens, where he made reference to pagan poets and philosophers (Acts 17:22-31). St. Augustine incorporated elements of Platonic thought into his theology, and St. Thomas Aquinas synthesized Aristotle and Christianity into a unified, consistent system of Christian thought (Scholasticism or Thomism).

Transubstantiation is predicated upon the distinction between two sorts of change: accidental and substantial. Accidental change occurs when non-essential outward properties are transformed in some fashion. Thus, water can take on the properties of solidity (ice) and gas (steam), all the while remaining chemically the same. A substantial change, on the other hand, produces something else altogether. An example of this is the metabolism of food, which becomes part of our bodies as a result of chemical and biological processes initiated by digestion. In our everyday experience, a change of substance is always accompanied by a corresponding transition of accidents, or properties.

In the Eucharist—a supernatural transformation—a substantial change occurs without accidental alteration. Thus, the properties of bread and wine continue after consecration, but their essence and substance cease to exist, replaced by the substance of the true and actual Body and Blood of Christ. It is this disjunction from the natural laws of physics which causes many to stumble (see John 6:60-69). See chart below.

Indeed, transubstantiation is difficult for the natural mind (especially with its modern excessively skeptical bent) to grasp and clearly requires a great deal of faith. Yet many aspects of Christianity which conservative, evangelical, orthodox Christians have no difficulty believing transcend reason and must ultimately be accepted on faith, such as: the Incarnation (in which a helpless infant in Bethlehem is God!), the Resurrection, the omniscience of God, the paradox of grace versus free will, eternity, the Union of the Human and Divine Natures in Christ (the Hypostatic Union), the Fall of Man and original sin, and the Virgin Birth, among many other beliefs. Transubstantiation may be considered beyond reason, yet it is not opposed to reason; suprarational, but not irrational, much like Christian theology in general.

If one accepts the fact that God became Man, then it cannot consistently be deemed impossible (as many casually assume) for Him to become truly and really present under the appearances of bread and wine. Jesus, after His Resurrection, could apparently walk through walls while remaining in His physical (glorified) body (John 20:26-27). How, then, can transubstantiation reasonably be regarded as intrinsically implausible by supernaturalist Christians?

Likewise, much of the objection to this doctrine seems to arise out of a pitting of matter against spirit, or, more specifically, an a priori hostility to the idea that grace can be conveyed through matter. This is exceedingly curious, since precisely this notion is fundamental to the Incarnation of our Lord Jesus. If God did not take on matter and human flesh, no one would have been saved. Such a prejudice is neither logical (given belief in the miraculous and Christian precepts) nor scriptural, as we shall see.

John Henry Cardinal Newman, whom very few would accuse of being unreasonable or credulous, had this to say about the “difficulties” of transubstantiation:

    People say that the doctrine of Transubstantiation is difficult to believe . . . It is difficult, impossible to imagine, I grant – but how is it difficult to believe? . . . For myself, I cannot indeed prove it, I cannot tell how it is; but I say, “Why should it not be? What’s to hinder it? What do I know of substance or matter? Just as much as the greatest philosophers, and that is nothing at all;” . . . And, in like manner: . . . the doctrine of the Trinity in Unity. What do I know of the Essence of the Divine Being? In know that my abstract idea of three is simply incompatible with my idea of one; but when I come to question the concrete fact, I have no means of proving that there is not a sense in which one and three can equally be predicated of the Inommunicable God. (23)

Once one realizes that transubstantiation is a miracle of God, any notion of impossibility vanishes, since God is omnipotent (all-powerful) and the sovereign Lord over all creation (Matthew 19:26, Philippians 3:20-21, Hebrews 1:3). If mere men can change accidental properties without changing substance (for example, turning iron into molten liquid or even vapor), then God is certainly able to change substance without outward transmutation.

Therefore, after these weak philosophical objections are disposed of, we can proceed to objectively and fairly examine the clear and indisputable biblical data which reveals to us that God does in fact perform (through the agency of priests) the supernatural act of transubstantiation.


1. Chapter 1: On the Real Presence of Our Lord Jesus Christ in the Most Holy Sacrament of the Eucharist. All Trent citations from Dogmatic Canons and Decrees, Rockford, IL: TAN Books and Publishers, 1977 (orig. 1912). See also: Catechism of the Catholic Church (CCC), Liguori, MO: Liguori Publications, 1994, #1373-1374, 1378-1381; Hardon, John A., Pocket Catholic Dictionary, NY: Doubleday Image, 1980, pp.132-3, 360.

2. Chapter 3: On the Excellency of the Most Holy Eucharist Over the Rest of the Sacraments. See also: CCC, #1377, 1390. This belief is derived largely from 1 Corinthian 11:27: “Whoever, therefore, eats the bread or drinks the cup of the Lord in an unworthy manner will be guilty of profaning the body and blood of the Lord.” Most NT translations include the crucial word or (e.g., NIV, NASB, NEB, NKJV, Phillips). The KJV is a notable exception, but many Protestant scholars admit that its and was a non-literal, polemical mistranslation.

3. Chapter 4: On Transubstantiation. See also: CCC, #1375-1376, 1413; Hardon, John A., The Catholic Catechism, Garden City, NY: Doubleday, 1975, p.161.

4. See Pope Paul VI, Encyclical Mysterium Fidei (On Eucharistic Doctrine and Worship), Glen Rock, NJ: Paulist Press, September 3, 1965, p.42.

5. Adam, Karl, The Spirit of Catholicism, tr. Dom Justin McCann, Garden City, NY: Doubleday Image, 1954 (orig. 1924 in German), p.18.

6. CCC, #1385-1387, 1415. See particularly 1 Corinthians 11:27-29; Vatican II: Constitution on the Sacred Liturgy, nos. 9, 11.

7. Vatican II: Lumen Gentium, 11; CCC, #1324, 1327.

8. CCC, #1322-1323, 1325-1326, 1331, 1348, 1353, 1369-1370, 1396, 1398, 1416.

9. CCC, #1329.

10. CCC, #1328, 1352, 1358-1361.

11. CCC, #1330, 1333, 1341, 1350, 1356-1357, 1362-1368, 1371-1372, 1382-1383, 1410.

12. CCC, #1330, 1343, 1345-1346, 1407.

13. CCC, #1332.

14. CCC, #1334-1335.

15. CCC, #1329, 1344, 1402.

16. CCC, #1347.

17. CCC, #1354, 1403-1404, 1409.

18. CCC, #1355, 1405.

19. CCC, #1378-1379, 1408, 1418.

20. CCC, #1391, 1416, 1419.

21. CCC, #1392-1395, 1416.

22. CCC, #1371, 1414.

23. Newman, John Henry, Apologia pro vita Sua {his religious autobiography}, Garden city, NY: Doubleday Image, 1956 (orig. 1864), p.318 (part 7: “General Answer to Mr. Kingsley”).

Eucharist Index / Main Index Copyright 1996 by Dave Armstrong. All rights reserved. Bible verses: RSV.

  • Aliquantillus

    Transubstantiation — or at least Aquinas’ explanation of this doctrine — faces a very fundamental difficulty. This difficulty is that after the change of the substance of bread into the substance of the body of Christ, this substance of Christ’s body doesn’t become the supporting subject of the bread accidents. Consequently, there’s no relation at all between these bread accidents and the body of Christ. They are two separate realities which show no mutual connection at all. For the bread accidents are held in existence by the sole power of God, without any supporting subject. Therefore these bread accidents are unrelated to the substance of the body of Christ. Hence it doesn’t seem to follow that consumption of these accidents by the communicant results in the reception of the body of Christ.

    • Dave Armstrong

      This is how St. Thomas Aquinas (since you say it is his difficulty) replied (Summa Theologica, Third Part, Q. 75, 4):

      Article 4. Whether bread can be converted into the body of Christ?

      Objection 1. It seems that bread cannot be converted into the body of Christ. For conversion is a kind of change. But in every change there must be some subject, which from being previously in potentiality is now in act. because as is said in Phys. iii: “motion is the act of a thing existing in potentiality.” But no subject can be assigned for the substance of the bread and of the body of Christ, because it is of the very nature of substance for it “not to be in a subject,” as it is said in Praedic. iii. Therefore it is not possible for the whole substance of the bread to be converted into the body of Christ.

      Objection 2. Further, the form of the thing into which another is converted, begins anew to inhere in the matter of the thing converted into it: as when air is changed into fire not already existing, the form of fire begins anew to be in the matter of the air; and in like manner when food is converted into non-pre-existing man, the form of the man begins to be anew in the matter of the food. Therefore, if bread be changed into the body of Christ, the form of Christ’s body must necessarily begin to be in the matter of the bread, which is false. Consequently, the bread is not changed into the substance of Christ’s body.

      Objection 3. Further, when two things are diverse, one never becomes the other, as whiteness never becomes blackness, as is stated in Phys. i. But since two contrary forms are of themselves diverse, as being the principles of formal difference, so two signate matters are of themselves diverse, as being the principles of material distinction. Consequently, it is not possible for this matter of bread to become this matter whereby Christ’s body is individuated, and so it is not possible for this substance of bread to be changed into the substance of Christ’s body.

      On the contrary, Eusebius Emesenus says: “To thee it ought neither to be a novelty nor an impossibility that earthly and mortal things be changed into the substance of Christ.”

      I answer that, As stated above (Article 2), since Christ’s true body is in this sacrament, and since it does not begin to be there by local motion, nor is it contained therein as in a place, as is evident from what was stated above (Article 1, Reply to Objection 2), it must be said then that it begins to be there by conversion of the substance of bread into itself.

      Yet this change is not like natural changes, but is entirely supernatural, and effected by God’s power alone. Hence Ambrose says [(De Sacram. iv): “See how Christ’s word changes nature’s laws, as He wills: a man is not wont to be born save of man and woman: see therefore that against the established law and order a man is born of a Virgin”: and] [The passage in the brackets is not in the Leonine edition] (De Myster. iv): “It is clear that a Virgin begot beyond the order of nature: and what we make is the body from the Virgin. Why, then, do you look for nature’s order in Christ’s body, since the Lord Jesus was Himself brought forth of a Virgin beyond nature?” Chrysostom likewise (Hom. xlvii), commenting on John 6:64: “The words which I have spoken to you,” namely, of this sacrament, “are spirit and life,” says: i.e. “spiritual, having nothing carnal, nor natural consequence; but they are rent from all such necessity which exists upon earth, and from the laws here established.”

      For it is evident that every agent acts according as it is in act. But every created agent is limited in its act, as being of a determinate genus and species: and consequently the action of every created agent bears upon some determinate act. Now the determination of every thing in actual existence comes from its form. Consequently, no natural or created agent can act except by changing the form in something; and on this account every change made according to nature’s laws is a formal change. But God is infinite act, as stated in I:7:1; III:26:2; hence His action extends to the whole nature of being. Therefore He can work not only formal conversion, so that diverse forms succeed each other in the same subject; but also the change of all being, so that, to wit, the whole substance of one thing be changed into the whole substance of another. And this is done by Divine power in this sacrament; for the whole substance of the bread is changed into the whole substance of Christ’s body, and the whole substance of the wine into the whole substance of Christ’s blood. Hence this is not a formal, but a substantial conversion; nor is it a kind of natural movement: but, with a name of its own, it can be called “transubstantiation.”

      Reply to Objection 1. This objection holds good in respect of formal change, because it belongs to a form to be in matter or in a subject; but it does not hold good in respect of the change of the entire substance. Hence, since this substantial change implies a certain order of substances, one of which is changed into the other, it is in both substances as in a subject, just as order and number.

      Reply to Objection 2. This argument also is true of formal conversion or change, because, as stated above (Reply to Objection 1), a form must be in some matter or subject. But this is not so in a change of the entire substance; for in this case no subject is possible.

      Reply to Objection 3. Form cannot be changed into form, nor matter into matter by the power of any finite agent. Such a change, however, can be made by the power of an infinite agent, which has control over all being, because the nature of being is common to both forms and to both matters; and whatever there is of being in the one, the author of being can change into whatever there is of being in the other, withdrawing that whereby it was distinguished from the other.

      Also, Third Part, Q. 75, 8:

      Article 8. Whether this proposition is false: “The body of Christ is made out of bread”?

      Objection 1. It seems that this proposition is false: “The body of Christ is made out of bread.” For everything out of which another is made, is that which is made the other; but not conversely: for we say that a black thing is made out of a white thing, and that a white thing is made black: and although we may say that a man becomes black still we do not say that a black thing is made out of a man, as is shown in Phys. i. If it be true, then, that Christ’s body is made out of bread, it will be true to say that bread is made the body of Christ. But this seems to be false, because the bread is not the subject of the making, but rather its term. Therefore, it is not said truly that Christ’s body is made out of bread.

      Objection 2. Further, the term of “becoming” is something that is, or something that is “made.” But this proposition is never true: “The bread is the body of Christ”; or “The bread is made the body of Christ”; or again, “The bread will be the body of Christ.” Therefore it seems that not even this is true: “The body of Christ is made out of bread.”

      Objection 3. Further, everything out of which another is made is converted into that which is made from it. But this proposition seems to be false: “The bread is converted into the body of Christ,” because such conversion seems to be more miraculous than the creation of the world, in which it is not said that non-being is converted into being. Therefore it seems that this proposition likewise is false: “The body of Christ is made out of bread.”

      Objection 4. Further, that out of which something is made, can be that thing. But this proposition is false: “Bread can be the body of Christ.” Therefore this is likewise false: “The body of Christ is made out of bread.”

      On the contrary, Ambrose says (De Sacram. iv): “When the consecration takes place, the body of Christ is made out of the bread.”

      I answer that, This conversion of bread into the body of Christ has something in common with creation, and with natural transmutation, and in some respect differs from both. For the order of the terms is common to these three; that is, that after one thing there is another (for, in creation there is being after non-being; in this sacrament, Christ’s body after the substance of bread; in natural transmutation white after black, or fire after air); and that the aforesaid terms are not coexistent.

      Now the conversion, of which we are speaking, has this in common with creation, that in neither of them is there any common subject belonging to either of the extremes; the contrary of which appears in every natural transmutation.

      Again, this conversion has something in common with natural transmutation in two respects, although not in the same fashion. First of all because in both, one of the extremes passes into the other, as bread into Christ’s body, and air into fire; whereas non-being is not converted into being. But this comes to pass differently on the one side and on the other; for in this sacrament the whole substance of the bread passes into the whole body of Christ; whereas in natural transmutation the matter of the one receives the form of the other, the previous form being laid aside. Secondly, they have this in common, that on both sides something remains the same; whereas this does not happen in creation: yet differently; for the same matter or subject remains in natural transmutation; whereas in this sacrament the same accidents remain.

      From these observations we can gather the various ways of speaking in such matters. For, because in no one of the aforesaid three things are the extremes coexistent, therefore in none of them can one extreme be predicated of the other by the substantive verb of the present tense: for we do not say, “Non-being is being” or, “Bread is the body of Christ,” or, “Air is fire,” or, “White is black.” Yet because of the relationship of the extremes in all of them we can use the preposition “ex” [out of, which denotes order; for we can truly and properly say that “being is made out of non-being,” and “out of bread, the body of Christ,” and “out of air, fire,” and “out of white, black.” But because in creation one of the extremes does not pass into the other, we cannot use the word “conversion” in creation, so as to say that “non-being is converted into being”: we can, however, use the word in this sacrament, just as in natural transmutation. But since in this sacrament the whole substance is converted into the whole substance, on that account this conversion is properly termed transubstantiation.

      Again, since there is no subject of this conversion, the things which are true in natural conversion by reason of the subject, are not to be granted in this conversion. And in the first place indeed it is evident that potentiality to the opposite follows a subject, by reason whereof we say that “a white thing can be black,” or that “air can be fire”; although the latter is not so proper as the former: for the subject of whiteness, in which there is potentiality to blackness, is the whole substance of the white thing; since whiteness is not a part thereof; whereas the subject of the form of air is part thereof: hence when it is said, “Air can be fire,” it is verified by synecdoche by reason of the part. But in this conversion, and similarly in creation, because there is no subject, it is not said that one extreme can be the other, as that “non-being can be being,” or that “bread can be the body of Christ”: and for the same reason it cannot be properly said that “being is made of [de] non-being,” or that “the body of Christ is made of bread,” because this preposition “of” [de] denotes a consubstantial cause, which consubstantiality of the extremes in natural transmutations is considered according to something common in the subject. And for the same reason it is not granted that “bread will be the body of Christ,” or that it “may become the body of Christ,” just as it is not granted in creation that “non-being will be being,” or that “non-being may become being,” because this manner of speaking is verified in natural transmutations by reason of the subject: for instance, when we say that “a white thing becomes black,” or “a white thing will be black.”

      Nevertheless, since in this sacrament, after the change, something remains the same, namely, the accidents of the bread, as stated above (Article 5), some of these expressions may be admitted by way of similitude, namely, that “bread is the body of Christ,” or, “bread will be the body of Christ,” or “the body of Christ is made of bread”; provided that by the word “bread” is not understood the substance of bread, but in general “that which is contained under the species of bread,” under which species there is first contained the substance of bread, and afterwards the body of Christ.

      Reply to Objection 1. That out of which something else is made, sometimes implies together with the subject, one of the extremes of the transmutation, as when it is said “a black thing is made out of a white one”; but sometimes it implies only the opposite or the extreme, as when it is said–“out of morning comes the day.” And so it is not granted that the latter becomes the former, that is, “that morning becomes the day.” So likewise in the matter in hand, although it may be said properly that “the body of Christ is made out of bread,” yet it is not said properly that “bread becomes the body of Christ,” except by similitude, as was said above.

      Reply to Objection 2. That out of which another is made, will sometimes be that other because of the subject which is implied. And therefore, since there is no subject of this change, the comparison does not hold.

      Reply to Objection 3. In this change there are many more difficulties than in creation, in which there is but this one difficulty, that something is made out of nothing; yet this belongs to the proper mode of production of the first cause, which presupposes nothing else. But in this conversion not only is it difficult for this whole to be changed into that whole, so that nothing of the former may remain (which does not belong to the common mode of production of a cause), but furthermore it has this difficulty that the accidents remain while the substance is destroyed, and many other difficulties of which we shall treat hereafter (III:77. Nevertheless the word “conversion” is admitted in this sacrament, but not in creation, as stated above.

      Reply to Objection 4. As was observed above, potentiality belongs to the subject, whereas there is no subject in this conversion. And therefore it is not granted that bread can be the body of Christ: for this conversion does not come about by the passive potentiality of the creature, but solely by the active power of the Creator.


      • Aliquantillus

        This is simply not an answer to the exact difficulty I mentioned. Please read my comment carefully. I have studied Aquinas extensively. In his writings he never addresses the apparent difficulty that after transsubstantion the body of Christ has no relation to the remaining accidents of the bread. For it is neither the supportive subject of these accidents, nor does it exercise any other causal function. I would appreciate a short answer which is really to the point instead of lengthy quotes that don’t address the real focus of my question.

        So what, in your opinion, is the relation between the accidents of the bread and the body of Christ after transusbstantiation?

The Coming Home Network International