Roman Catholic Transubstantiation


Roman Catholic Brother and Sisters in Christ,

I have no interest here to debate but wish very much to understand. I would like to gain a better understanding of your views on transubstantiation. In the past, I thought I had a good understanding of it but I have this feeling I am woefully deficient. I am curious if this statement to the best of your knowledge is true:

During Roman Catholic Mass, at the consecration during Communion, the elements of the Eucharist, bread and wine, are transformed into the actual body and blood of Jesus. They are then no longer bread and wine but only retain their appearance of bread and wine.

Is this true? I think I am trying to see where Consubstantiation ends and where Transubstantiation ends (please forgive me if this is a poor wording).

Thanks and Peace!


You are correct. Read the Catechism of the Catholic Church on the Eucharist here:


My familiarity with the doctrine of consubstantiation is somewhat limited but my understanding is that it holds that the substance of the bread and the wine remain **along side ** of the body and blood of Christ as opposed to transubstantiation which hold that the subtance of the bread and the wine no longer remains but has been replaced (changed into) the body and blood of Christ.


Consubstantiation cannot be true for material substances because two material substances cannot occupy the same space materially.

Consubstantiation is true as far as God the Father and God the Son, as we say in the Creed at Mass, because they are one in substance / essence / being, and two persons.

We hear the priest saying “This is my body,… the chalice of my blood…” and we understand that the Son of God is knowing those words as his words and his will at that moment. He is knowing what you see on the altar as his body, and next to it his blood. He is knowing his death and sacrifice at that moment as his real death and sacrifice, with that body and blood next to each other on the altar.

What God knows is the actuality of reality. We are in the upper room at that moment because the Son of God is knowing this. We are at the cross at that moment with his blood drained from his side, because He is knowing this in his Godhead.

We like to say it happens at the moment of the priests consecration, yet what is really happening at the moment of the consecration is that Jesus is knowing his death, and suddenly we are where he knows his body and blood are at. And he knows this until we consume this sacrifice as our part of our covenant with him.


I suggest you read what the Appostolic Fathers wrote about the matter. Cant get much closer to the real meaning in the eucharist than from the men who took their study directly from the appostles and were ordained by them personally to continue the message and authentic faith to the next generation.

The Didache or “The Teaching of the Twelve Apostles” is a manuscript which was used by 2nd century bishops and priests for the instruction of catechumens. Many early Christian writers have referenced it making this document relatively easy to date.
“Let no one eat and drink of your Eucharist but those baptized in the name of the Lord; to this, too the saying of the Lord is applicable: ‘Do not give to dogs what is sacred’”.
-Ch. 9:5

“On the Lord’s own day, assemble in common to break bread and offer thanks; but first confess your sins, so that your sacrifice may be pure. However, no one quarreling with his brother may join your meeting until they are reconciled; your sacrifice must not be defiled. For here we have the saying of the Lord: ‘In every place and time offer me a pure sacrifice; for I am a mighty King, says the Lord; and my name spreads terror among the nations.’”

***St. Clement *was the third successor of Peter as Bishop of Rome; otherwise known as the third Pope

“Since then these things are manifest to us, and we have looked into the depths of the divine knowledge, we ought to do in order all things which the Master commanded us to perform at appointed times. He commanded us to celebrate sacrifices and services, and that it should not be thoughtlessly or disorderly, but at fixed times and hours. He has Himself fixed by His supreme will the places and persons whom He desires for these celebrations, in order that all things may be done piously according to His good pleasure, and be acceptable to His will. So then those who offer their oblations at the appointed seasons are acceptable and blessed, but they follow the laws of the Master and do not sin. For to the high priest his proper ministrations are allotted, and to the priests the proper place has been appointed, and on Levites their proper services have been imposed. The layman is bound by the ordinances for the laity.”

Source: St. Clement, bishop of Rome, 80 A.D., to the Corinthians

“Our sin will not be small if we eject from the episcopate those who blamelessly and holily have offered its Sacrifices.”

Source: Letter to the Corinthians, [44,4]

***St. Ignatius *became the third bishop of Antioch, succeeding St. Evodius, who was the immediate successor of St. Peter. He heard St. John preach when he was a boy and knew St. Polycarp, Bishop of Smyrna. Seven of his letters written to various Christian communities have been preserved. Eventually, he received the martyr’s crown as he was thrown to wild beasts in the arena

“Consider how contrary to the mind of God are the heterodox in regard to the grace of God which has come to us. They have no regard for charity, none for the widow, the orphan, the oppressed, none for the man in prison, the hungry or the thirsty. They abstain from the Eucharist and from prayer, because they do not admit that the Eucharist is the flesh of our Savior Jesus Christ, the flesh which suffered for our sins and which the Father, in His graciousness, raised from the dead.”

“Letter to the Smyrnaeans”, paragraph 6. circa 80-110 A.D.

“Come together in common, one and all without exception in charity, in one faith and in one Jesus Christ, who is of the race of David according to the flesh, the son of man, and the Son of God, so that with undivided mind you may obey the bishop and the priests, and break one Bread which is the medicine of immortality and the antidote against death, enabling us to live forever in Jesus Christ.”

-“Letter to the Ephesians”, paragraph 20, c. 80-110 A.D.

“I have no taste for the food that perishes nor for the pleasures of this life. I want the Bread of God which is the Flesh of Christ, who was the seed of David; and for drink I desire His Blood which is love that cannot be destroyed.”

-“Letter to the Romans”, paragraph 7, circa 80-110 A.D.

“Take care, then who belong to God and to Jesus Christ - they are with the bishop. And those who repent and come to the unity of the Church - they too shall be of God, and will be living according to Jesus Christ. Do not err, my brethren: if anyone follow a schismatic, he will not inherit the Kingdom of God. If any man walk about with strange doctrine, he cannot lie down with the passion. Take care, then, to use one Eucharist, so that whatever you do, you do according to God: for there is one Flesh of our Lord Jesus Christ, and one cup in the union of His Blood; one altar, as there is one bishop with the presbytery and my fellow servants, the deacons.”

-Epistle to the Philadelphians, 3:2-4:1, 110 A.D.



**St. Irenaeus succeeded **St. Pothinus to become the second bishop of Lyons in 177 A.D. Earlier in his life he studied under St. Polycarp. Considered, one of the greatest theologians of the 2nd century, St. Irenaeus is best known for refuting the Gnostic heresies.

[Christ] has declared the cup, a part of creation, to be his own Blood, from which he causes our blood to flow; and the bread, a part of creation, he has established as his own Body, from which he gives increase to our bodies."
Source: St. Irenaeus of Lyons, Against Heresies, 180 A.D.:

“So then, if the mixed cup and the manufactured bread receive the Word of God and become the Eucharist, that is to say, the Blood and Body of Christ, which fortify and build up the substance of our flesh, how can these people claim that the flesh is incapable of receiving God’s gift of eternal life, when it is nourished by Christ’s Blood and Body and is His member? As the blessed apostle says in his letter to the Ephesians, ‘For we are members of His Body, of His flesh and of His bones’ (Eph. 5:30). He is not talking about some kind of ‘spiritual’ and ‘invisible’ man, ‘for a spirit does not have flesh an bones’ (Lk. 24:39). No, he is talking of the organism possessed by a real human being, composed of flesh and nerves and bones. It is this which is nourished by the cup which is His Blood, and is fortified by the bread which is His Body. The stem of the vine takes root in the earth and eventually bears fruit, and ‘the grain of wheat falls into the earth’ (Jn. 12:24), dissolves, rises again, multiplied by the all-containing Spirit of God, and finally after skilled processing, is put to human use. These two then receive the Word of God and become the Eucharist, which is the Body and Blood of Christ.”

-“Five Books on the Unmasking and Refutation of the Falsely Named Gnosis”. Book 5:2, 2-3, circa 180 A.D.

“For just as the bread which comes from the earth, having received the invocation of God, is no longer ordinary bread, but the Eucharist, consisting of two realities, earthly and heavenly, so our bodies, having received the Eucharist, are no longer corruptible, because they have the hope of the resurrection.”

-“Five Books on the Unmasking and Refutation of the Falsely named Gnosis”. Book 4:18 4-5, circa 180 A.D.


Yes, your understanding of transubstantian is correct.



Thanks very much everyone for helping me with this especially the Catechism link – appears I missed this. It is very much appreciated.

It would probably be good to get a Consubstantiationist’s opinion on how they believe God’s Spirit (and thereby Himself – I am assuming) imbues the bread and wine at their Communions as I think you offer a valid physical point in the quote above.

*Again apologies if my terms do not adequately describe or offend.


They are not transformed. If they were transformed then there would be a tangible change in their appearance. They are transubstantiated, that is, changed in substance.


Very good explanation and observation, Elizium! Appreciate that very much.


I think you mean third successor, or the fourth Pope: Peter; Linus; Anacletus; Clement.

Great quotes!


Consubstantiation is not an imbue (permeate with a quality) but a conversion, as the Catechism shows:1375 It is by the conversion of the bread and wine into Christ’s body and blood that Christ becomes present in this sacrament. The Church Fathers strongly affirmed the faith of the Church in the efficacy of the Word of Christ and of the action of the Holy Spirit to bring about this conversion. Thus St. John Chrysostom declares: [INDENT] It is not man that causes the things offered to become the Body and Blood of Christ, but he who was crucified for us, Christ himself. The priest, in the role of Christ, pronounces these words, but their power and grace are God’s. This is my body, he says. This word transforms the things offered. 204
And St. Ambrose says about this conversion: Be convinced that this is not what nature has formed, but what the blessing has consecrated. The power of the blessing prevails over that of nature, because by the blessing nature itself is changed. . . . Could not Christ’s word, which can make from nothing what did not exist, change existing things into what they were not before? It is no less a feat to give things their original nature than to change their nature. 205
204 St. John Chrysostom, prod. Jud. 1:6:PG 49,380.
205 St. Ambrose, De myst. 9,50; 52:PL 16,405-407.


We understand them as transubstantiated due to it being a gift of Christ to give his physical substance to us to consume (eat and drink) so that our senses chew and swallow his flesh and blood literally, as commanded. Then in our intellect, our souls, we understand we as full humans (both body and soul) are taking Jesus into ourselves - the body eats a substance that the soul now “knows” present within, being where the body and blood are.


Here I meant to say Transubstantiation, however consubstantiation is described here in FROM CONFLICT TO COMMUNION, Lutheran-Catholic Common Commemoration of the Reformation in 2017:
143. Luther understood Christ’s body and blood to be present “in, with, and under” the species of bread and wine. There is an exchange of properties (communicatio idiomatum) between Christ’s body and blood and the bread and wine. This creates a sacramental union between bread and Christ’s body, and the wine and Christ’s blood. This new type of union, formed by the sharing of properties, is analogous to the union of the divine and human natures in Christ. Luther also compared this sacramental union to the union of iron and fire in a fiery iron.


In order to understand Transubstantiation you must understand the principles used in Thomistic theology and philosophy. Which means having a basic understanding of Thomas’ application of Aristotelian metaphysics. You must understand what matter and form are, substance and accidents, and how they come into play during the consecration. Before the consecration you have actual bread and wine in substance along with their accidents. So you begin with the substance of bread and wine along with their accidents. The substance it what that something is, while the accidents are its characteristics which include appearances, etc. Normally a thing in its essence contains a relationship between the substance and accidents.

Two actual miracles happen during the consecration. First the substance of the actual bread and wine are changed into the actual Body and Blood of Christ, Body Blood Soul and Divinity. That is, the bread and wine are no longer, and the Body and Blood of Christ are put in their place. As Trent defined, we have a conversion of the whole substance. However, the second miracle is that the accidents of the bread and wine remain. Otherwise you would have no way of identifying the Body and Blood of Christ. They are hidden under the accidents of the bread and wine, which is what you are physically touching. So you are actually receiving the actual Body and Blood of Christ, hidden under the accidents of the bread and wine.

I recommend reading Trent and St. Thomas to learn more details.


Very good, we must keep repeating this forever - as we have been doing.



Modern Catholic Dictionary:

“Supernaturally, accidents can exist, in the absence of their natural substance, as happens with the physical properties of bread and wine after Eucharistic consecration.”


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