Transubstantiation: 10 Questions on the Substance of the Holy Eucharist

“Jesus Christ is whole and entire both under the form of bread and under the form of wine.”

"The Last Supper" by James J. Tissot

Listers, the following lesson is taken from the Baltimore Catechism. The Baltimore Catechism was the standard catechism of teaching the faith and catechizing children from 1885 to Vatican II. Its basic question-and-answer approach is the most natural learning style for the human mind and simplifies even the most complex theological questions. SPL has also reproduced 29 Questions Explaining Indulgences, 46 Questions to Help Explain the Sacraments,and What Is Meant By the “End of Man” and 10 other Questions.

The following list is the second installment of questions explaining the Eucharist. The first collection of questions can be found in the list: This Is My Body: 10 Questions to Help Explain the Holy Eucharist.


Baltimore Catechism No. 3

On the Holy Eucharist 878-887


Q. 878. How do we know that it is possible to change one substance into another?

A. We know that it is possible to change one substance into another, because:

God changed water into blood during the plagues of Egypt.
Christ changed water into wine at the marriage of Cana.
Our own food is daily changed into the substance of our flesh and blood; and what God does gradually, He can also do instantly by an act of His will.


Q. 879. Are these changes exactly the same as the changes that take place in the Holy Eucharist?

A. These changes are not exactly the same as the changes that take place in the Holy Eucharist, for in these changes the appearance also is changed, but in the Holy Eucharist only the substance is changed while the appearance remains the same.


Q. 880. How do we show that Christ did change bread and wine into the substance of His body and blood?

A. We show that Christ did change bread and wine into the substance of His body and blood:

From the words by which He promised the Holy Eucharist;
From the words by which He instituted the Holy Eucharist;
From the constant use of the Holy Eucharist in the Church since the time of the Apostles;
From the impossibility of denying the Real Presence in the Holy Eucharist, without likewise denying all that Christ has taught and done; for we have stronger proofs for the Holy Eucharist than for any other Christian truth.


Q. 881. Is Jesus Christ whole and entire both under the form of bread and under the form of wine?

A. Jesus Christ is whole and entire both under the form of bread and under the form of wine.


Q. 882. How do we know that under the appearance of bread we receive also Christ’s blood; and under the appearance of wine we receive also Christ’s body?

A. We know that under the appearance of bread we receive also Christ’s blood, and under the appearance of wine we receive also Christ’s body; because in the Holy Eucharist we receive the living body of Our Lord, and a living body cannot exist without blood, nor can living blood exist without a body.


Q. 883. Is Jesus Christ present whole and entire in the smallest portion of the Holy Eucharist, under the form of either bread or wine?

A. Jesus Christ is present whole and entire in the smallest portion of the Holy Eucharist under the form of either bread or wine; for His body in the Eucharist is in a glorified state, and as it partakes of the character of a spiritual substance, it requires no definite size or shape.


Q. 884. Did anything remain of the bread and wine after their substance had been changed into the substance of the body and blood of our Lord?

A. After the substance of the bread and wine had been changed into the substance of the body and blood of Our Lord, there remained only the appearances of bread and wine.


Q. 885. What do you mean by the appearances of bread and wine?

A. By the appearances of bread and wine I mean the figure, the color, the taste, and whatever appears to the senses.


Q. 886. What is this change of the bread and wine into the body and blood of our Lord called?

A. This change of the bread and wine into the body and blood of Our Lord is called Transubstantiation.


Q. 887. What is the second great miracle in the Holy Eucharist?

A. The second great miracle in the Holy Eucharist is the multiplication of the presence of Our Lord’s body in so many places at the same time, while the body itself is not multiplied — for there is but one body of Christ.

  • Joseph Bimbi

    Festival of eating actual human body and of drinking actual human blood? Sorry, I cannot help thinking it as pure cannibalistic festival!

    • Gary Simmons

      Which is *exactly* what the pagan Romans thought, as well. Nobody would get that impression from a Protestant service, ergo, the ancient pagan Romans could not have been responding to a Protestant service, but a Catholic one.

  • Jon

    “for we have stronger proofs for the Holy Eucharist than for any other Christian truth.”

    Really? As a protestant, I’m finding it very difficult to see any proof at all. It is possible to change one substance into another – I’ve no problem with that. But what proof is there that Jesus actually did change the substance of the Last Supper, or that he conferred that same ability onto the Apostles? The fact that it is believed to be so by Catholic Tradition is not in itself proof, and the wording of the gospels does not directly support transubstantiation in any way. So where and why did this belief start?

    Isn’t it important to clarify why something is believed before delving into the specifics of the belief? Whether the whole host is changed is a secondary matter to whether the host changes at all.

    • Anonymous

      Jesus identified himself as the “living bread that has come down from heaven” given by God the Father. (John 6:51) He called himself the “bread of life,” which, if eaten, gave eternal life. (John 6:31) He stated in no uncertain terms that the “bread which I am to give,” was his “flesh,” the “flesh of the Son of Man,” and that, unless a man “eat the flesh of the Son of Man, and drink his blood,” he would have no spiritual life. (John 6:52, 54-55) This was “God’s gift of bread” that came “down from heaven,” and would give “life to the whole world.” (John 6:33)

      Those words of promise came to reality when Jesus, at the Last Supper, uttered the words of Institution over the bread–“This is my body”–and over the wine–“This is my blood.” (Matt. 26:26-28; see also Mark 14:22-24; Luke 22:19-20)

      Two sets of four words: eight words in all. In his marvelous hymn Pange Lingua, St. Thomas caught the gist of this remarkable historical grace-event ushered in by eight simple words: se dat suis manibus, Jesus gave himself with his hands. This is pure St. Augustine: Jesus, Augustine says, “carried himself when he said, ‘this is my Body.'” (Enarr. in Ps., 33.II)

      St. Paul recognized the import of Jesus’ words of Institution when wrote to the Corinthians that they eat and drink damnation to themselves if they eat and drink the “Lord’s body and blood” unworthily, not recognizing or discerning the Lord’s body in the Sacrament of the Eucharist. (1 Cor. 11:27-29)

      There is no room for doubt that the early Church, maintaining the apostolic doctrine learned from none other than Jesus himself, understood that the bread and wine, after the words of Institution were uttered over them by the bishop or priest, became, in reality, the Body and Blood of Jesus Christ. Francis Beckwith has called this belief by the early Church Eucharistic realism.

      Witness, as just one example of myriads that could be cited of this Eucharistic realism, the yearning of St. Ignatius of Antioch in his Letter to the Romans written around 110 A.D. Though in chains and being taken to sure martyrdom, he desired to celebrate the Eucharist which he described thus: “I desire the Bread of God, the heavenly Bread, the Bread of Life, which is the flesh of Jesus Christ, the Son of God . . . . I wish the drink of God, namely His blood, which is incorruptible love and eternal life.”

      Witness also the words of St. Cyril of Jerusalem (ca. 313-386 A.D.) to his catechumens, as he taught them that before the consecration there existed “simple bread and wine,” but after the consecration the “bread becomes the Body of Christ, and the wine the Blood of Christ.” After the consecration, he explained, the bread and the wine were not to be considered “bare elements, for they are, according to the Lord’s declaration, the Body and Blood of Christ.” He tells the catechumens not to judge by “sense,” or by “taste,” but to grasp the truth by “faith,” and so be “fully assured without misgiving” of Christ’s Real Presence under the veils of bread and wine. (Cat. Lects., 19.7; 22.6)

      The witness of the Church Fathers which, when added to the clear message in the Scriptures, testify monolithically that the Real Presence of Christ in the Eucharist is part of the oral and written “traditions” received by the apostles from Jesus, handed down by them, and part of the early Church’s faith. (cf. 2 Thess. 2:15) It is revealed truth.

      To be sure, the Real Presence is a mystery–the mysterium fidei–the mystery of faith, as it is frequently referred to. Simply put, it is the belief that, after the words of consecration, Jesus is really, substantially, ontologically, essentially and entirely present, Body and Soul, Humanity and Divinity under the species, or under the accidents, or “under the veil” in Cardinal Newman’s words, of bread and wine which no longer have any substantive reality as bread or wine.

      Christ’s Real Presence has presented a stumbling block to those weak in faith, to those who rely on their senses or their reason alone to circumscribe God, and so seek to bind God to a lesser truth (their own), and thereby limit the power and presence and design of the Word of God.

      The Church, however, loyal to the Word made flesh, recognizes like the poet John Dryden that some truths–mysteries of the Faith, in particular, of which the Real Presence is one–are truths beyond the senses and beyond reason, though without contradicting their witness. God is not confined to a box of sensory perception and human reason. If one can comprehend it with the senses and with reason, it is not God.

      To limit God to what we learn from our senses and our reason is to make God a creature, to put God in a cage of sense and reason, to domesticate God. It is to naturalize the supernatural, to tame the Divine. It is also to emasculate faith, which is intended to take us way beyond human senses and human reason to another order altogether–the supernatural order. “Faith is the evidence of things not seen!” (Heb. 11:1)

      But God, so wildly in love with us, will not be leashed by human weakness.

      Can I my reason to my faith compel,
      And shall my sight, and touch, and taste rebel?
      Superior faculties are set aside;
      Shall their subservient organs be my guide?

      The Church answers Dryden’s questions with an unequivocal “No!”

      The Catholic Church takes the “is” in the words of the Lord, “This is my body” and “This is my blood,” to mean, very simply, “is.” In varying degrees, those who rely too much on senses, or whose faith is too rationalistic, or who are just plain misinformed or misguided and so reject the dogma of the Church parse words and equivocate like President Clinton in his notorious statement: “It depends upon what the meaning of the word ‘is’ is.”

      Sadly, those without the faith of the Church don’t take Jesus at his word when he uses the word “is,” but cavil, argue, quibble, wriggle, invoke nuance so as to have the word “is” mean anything else but “is.” If sincere, they might be, like the Roman Catechism charitably puts it, “possibly . . . overwhelmed” by the “greatness” of this mystery.

      But let us not belittle the gift of God! “If you knew the gift of God!” said Jesus to the Samaritan woman at the well, and, we might be sure, to those who deny the Real Presence of Christ in the Eucharist. (John 4:10)

      In responding over the centuries to efforts to “cavil, argue, quibble, wriggle, and invoke nuance” regarding the word “is,” the word the Church ultimately selected to protect this very simple and unwavering belief that “is” means “is” and nothing less than “is,” is “transubstantiation.” It is therefore a word worth exploring in our series Tres Linguae Sacrae.

      “Because Christ our Redeemer said that it was truly his body that he was offering under the species of bread,” the Church declared at the Council of Trent, “it has always been the conviction of the Church of God, and this holy council now again declares, that, by the consecration of the bread and wine, there takes a change of the whole substance of bread into the substance of the body of Christ our Lord and of the whole substance of wine into the substance of his blood. This change the holy Catholic Church has fittingly and properly named transubstantiation.” (DS 1642)

      The Council of Trent defended Catholic Eucharistic doctrine against the attacks of the Protestant reformers, but it drew from its patrimony when it used the word “transubstantiation,” a word first used by theologians to description the faith of the fathers in earlier controversies, and later adopted by the Church as descriptive of what occurs when the bread and wine are consecrated as when used by Pope Innocent III (1208 A.D.), the Fourth Lateran Council (1215), the Second Council of Lyons (1274), and the Council of Florence (1439). (DS 782, 802, 860, 1321)

      The word transubstantiation therefore had a centuries-old pedigree by the time it was used in the Council of Trent, though the truth it encapsulated was there in Christ’s simple evangelical word “is.”

      The “dogma of transubstantiation,” as Pope Paul VI called it in his encyclical on the Eucharist, Mysterium Fidei, No. 10, is a “perennially valid teaching,” says Blessed John Paul II in his Encyclical on the Eucharist, Ecclesia de Eucharistia, No. 15. The word transubstantiation ought to be worn proudly, like a badge of fidelity to the Lord.

      Section 1413 of the current Catechism of the Catholic Church insists on it as the means by which Jesus Christ “living and glorious” makes his appearance at Mass: “By the consecration the transubstantiation of the bread and wine into the Body and Blood of Christ is brought about. Under the consecrated species of bread and wine, Christ himself, living and glorious, is present in a true, real, and substantial manner: his Body and Blood, with his soul and his divinity.”

      The word transubstantiation comes from Latin, transubstantiatio, a word formed by the prefix trans (meaning “across”) and substantia (meaning “substance”). Literally, therefore, it means to undergo a change from one substance to another substance, which precisely describes the faith of the Church when it comes to her understanding of what happens at the words of consecration at Mass.

      The concept of transubstantiation draws vaguely and loosely from Aristotelian metaphysics, but also absolutely revolutionizes Aristotle, since Aristotle had no notion of transubstantiation, only of the categories of substances and accidents. Aristotle, moreover, would never have even imagined that the accidents of bread and wine “continue without a subject,” through the direct power of God, who as creator of “both substance and accident, can by His unlimited power preserve an accident in existence when the substance is withdrawn whereby it was preserved in existence,” as St. Thomas Aquinas put it in his Summa Theologia. S.T. IIIa, q. 77, art. 1, c.

      That the Church draws from where she can, including pagan philosophers if need be, to preserve or develop the faith ought not to bother us. This is not unlike the Church in other areas, for example, in its adoption of the word persona (Greek: prosopon) to describe the dogma of the Trinity, or in its elaboration of the natural moral law, which, based upon St. Paul’s inspired lead in his letter to the Romans (Rom. 2:14), she selectively borrowed from the Stoic philosophers, but in taking it entirely transformed it.

      Substance is one of Aristotle’s ten categories (or praedicamenta), in fact the most fundamental category. A thing’s substance (in Greek οὐσία or ousia) is the what it is (τὸ τί ἐστι or to ti esti), its essence, its most fundamental reality. The other nine categories were called accidents (in Greek συμβεβηκός or symbebēkos), relations or qualities or aspects of a substance that did not essentially change it or its reality, but that modified it. (See Categories 4, 1b25-2a4; Topics 1.9, 103b20-25)

      Accidents are things that can be said of a substance. For example, a black dog and a brown dog, or a big dog and a small dog, share the same substance, but they differ in the accidental quality of color and/or the quantity of size. In Aristotle’s view, accidents need a substance, and cannot exist on their own. There is no such reality as “big” or “brown” without reference to something big or something brown.

      So, in Aristotelian terms but certainly way beyond even the wildest of Aristotelian imaginings, after the consecration, only the “accidents” of bread and wine remain; however, the “substance” is no longer bread and wine, but rather the entire Christ, Body and Soul, Humanity and Divinity.

      The insights of Aristotle are not needed to understand transubstantiation. As Pope Paul VI described it in his Encyclical on the Eucharist Mysterium Fidei:

      “As a result of transubstantiation, the species [what appears] of bread and wine . . . contain a new ‘reality’ which we can rightly call ontological [in other words, involves the order being, reality, essence]. For what now lies beneath the aforementioned species is not what was there before, but something completely different; and not just in the estimation of Church belief but in reality, since once the substance or nature of the bread and wine has been changed into the body and blood of Christ, nothing remains of the bread and the wine except for the species-beneath which Christ is present whole and entire in His physical ‘reality,’ corporeally present, although not in the manner in which bodies are in a place.” Mysterium Fidei, No. 46.

      There is not a whiff of Aristotle here; rather, there is nothing but fidelity to Jesus, a striving in faith to understand him without quibble when he chose that splendid and simple word “is” in those two splendid and simple four-word-phrases that have the power to change the world as they have the power to change bread and the power to change us: “This is my body,” and “This is my blood.”

      In the words of John Dryden in his poem “The Hind and the Panther,” the word transubstantiation “loosed the tongue,” and with the tongue the human mind, “to explain,” in the best human words available (and it does not matter where they came from), what our Catholic “forefathers meant by real presence in the sacrament.”

      What is absolutely crucial to understand is this: the dogma of transubstantiation is nothing less than what Jesus intended when he said those words–his dying declaration, his testament, his words of life–the night before he died: “This is my body.” “This is my blood.” To believe in the dogma of transubstantiation is to believe Christ. Knowingly to reject the dogma of transubstantiation is to deny him.

      “This is a hard saying,” some say. Perhaps. “Does this,” the word transubstantiation and what it means, “offend you?” Jesus still asks. (Cf. John 6:61) Sadly, to some it does offend, and they have turned away. Happily, others respond like St. Peter: “Lord, to whom shall we go? You have the words of eternal life.” (John 6:68)

      The dogma of transubstantiation helps us understand how something that looks, smells, tastes, and feels like bread and wine before the consecration as well as after the consecration can be–really, truly, substantially, essentially–something entirely and beautifully Other than it seems to our feeble senses and reason.

      Yes. This mystery’s greatness very possibly overwhelms. But it is precisely the overwhelming greatness of this mystery described by the dogma of transubstantiation that allows Saint Thérèse of Lisieux to say these beautiful and most simple words: “I cannot fear a God who made himself so small for me!”

      There it is: the ineffability of the word “is” when used by the Lord, and the dogma of transubstantiation which forms a redoubt erected around the simple and defenseless word “is” so as to protect it from anyone, large or small, wise or foolish, rich or poor, sincere or insincere who dares contradict the Lord and make “is” anything less than “is.” The omnipotent, overwhelming, omniscient, infinite, and eternal God makes Himself small, for you, and for me. That is why, if we approach the Eucharistic Lord worthily, we cannot fear Him.

      Transubstantiation. This is a truth to live for. This is a truth to die for.

  • ValB

    Transubstantiation…I have difficulty spelling it and saying it never mind grasping it. But there are some things that we will never totally understand when it comes to our faith. God is incomprehensible and Christ is our way of achieving a measure of peace in this existence, even if we can’t understand God. The only real way to experience the grace of Christ in the eucharist, is to take it on a regular basis, with an open mind and will to let it change you. The process of change that occurs with this action is slow and steady. It becomes the most significant part of your life because you slowly start to understand Christ and what he means to humanity. I highly recommend it.

  • Michele

    I think Anonymous’ and Valb’ replies are on the mark and why I am no longer a Protestant.

  • McMalachy

    What a tremendous contribution by anonymous. I understand more clearly now that Jesus gifted his glorified body under the apppearance of bread and wine, and that he required that all Christians avail of this gift.

  • McMalachy

    As a child I had no problem with receiving Holy Communion, I saw it as a gift from God to help me in my life, I had peace after receiving Communion. In the last many years though, I struggle with anxiety before and after I go to the altar rails, as I am afraid of the power of Almighty God, and am alarmed to have taken that power within myself.

    Can you point me to something I can do or read to help me receive Holy Communion in peace as I previously did? (I have been to Confession and have no large sins that I worry about.)

    Thanks for the good work on this website.

  • McMalachy

    Here I am six weeks later and the answer has come to me, through prayer and reflection. I am afraid to get too close to God in Holy Communion, because I fear that I can’t rely on God’s love. This is because I don’t understand why God would love me. What I don’t understand I don’t trust. What I don’t trust I stay away from. This is a clear sign that although I love God, I don’t trust Him. I believe that God is absolutely trustworthy so I will trust Him. He doesn’t need my permission to love me.