Real presence in Eucharist



It is not something that can be easily conceptualized. However, if we consider that God created the world out of nothing, that He caused the whole being, the form and matter for instance of water, of created things to be from nothing, it is certainly not beyond his infinite power that he can change the whole substance of one thing into the whole substance of some other thing. We may be able to take as an analogy the instance where Jesus changed the water into wine at the wedding in Cana. This can be conceptualized as Jesus changing the being of water into the being of wine.

The appearance of the uranium in a nuclear reactor as you describe it is not going to come from nothing. The matter in the plutonium is the same matter that was in the uranium whether the matter of the uranium turned into energy as science might call it and then back again into matter or mass. In modern scientific theory you have mass = energy = mass as well as the conservation of mass and the conservation of energy in which they say that neither mass or energy is created or destroyed. In transubstantiation, there is no common subject that was in the substance of the bread or wine that is also in the substance of the body and blood of Christ after the conversion of the elements, neither of the form or matter.

Blood remains blood whether it is carrying carbon dioxide or oxygen and the red blood cells which are a part of the blood and which do the work of carrying carbon dioxide and oxygen remain red blood cells whether they are carrying carbon dioxide or oxygen. There is no substantial change going on here. Nor are the carbon dioxide and oxygen elements converted into one another.


Thank you, @Richca. I didn’t realize, when I asked my question, that it meant I was putting you to the trouble of writing such a full and detailed explanation. My apologies for that.

I have a follow-up question to ask you, but it’s too late here now. I need to think about it carefully and I’ll post it tomorrow.


My concern here is not so much the Catholic doctrine of transubstantiation in itself, as the usefulness of the term in discussing the question with non-Catholics. In other words, I’m approaching it not so much as a question of theology, or even of philosophy, as of language.

In the case of the cow that turns grass into milk, the word is “metabolism”. In the case of the consecration of the bread and the wine, the word is “transubstantiation”. If someone asks how metabolism works, you can answer the question using terms such as “proteins” and “vitamins”, and then if they ask what a protein is, you can explain that, too. But that is not paralleled in the case of transubstantiation. As you say, “The substantial change which we call transubstantiation and which occurs at the consecration of the bread and wine at Mass is a one of a kind substantial change, there is no other instance of this kind of substantial change in the whole created order operating through the natural laws of nature. .… In transubstantiation, there is no common subject that was in the substance of the bread or wine that is also in the substance of the body and blood of Christ after the conversion of the elements, neither of the form or matter.”

These two statements, I think, lead to the following conclusion. Faced with a disbeliever – either a Protestant (Calvinist?) who says No, it’s only a memorial ceremony, or an atheist who says it’s not even that – the word “transubstantiation” doesn’t provide you, as far as I can see, with any argument that would help you to answer their questions such as, How does it work? What is going on beneath the surface? How do you know that what you say is true?

Am I missing something here?


For myself, I don’t think so. Transubstantiation is not amenable to proof or verification. Because, of course, all that we can perceive are accidents, never substance. No one can say “how” it works, except by the power of Christ through his sacrament.

The only proof one can offer is the words of Christ, who offering the bread at the last supper, said “This IS my body,” and offering the cup, said “This IS my blood.” John 6 is of course also persuasive. Jesus never offered an explanation, but he refused to retract his words or explain them away as metaphorical. On the road to Emmaus, the two disciples did not recognize him except “in the breaking of the bread.”


Thank you, @JimG.


[quote=“BartholomewB, post:163, topic:466316, full:true”]

These two statements, I think, lead to the following conclusion. Faced with a disbeliever – either a Protestant (Calvinist?) who says No, it’s only a memorial ceremony, or an atheist who says it’s not even that – the word “transubstantiation” doesn’t provide you, as far as I can see, with any argument that would help you to answer their questions such as, How does it work?

Well, the word metabolism doesn’t provide one, as far as I can see, with how metabolism works. The definition in the dictionary gives a general idea of what it refers too, a biological or physiological process. The etymology of metabolism (from etymolonline) comes from ‘meta-’ change + ‘ballein’ to throw. Not much to go on here. In this sense, I think the word transubstantiation from its latin roots is more meaningful as it essentially means a change of substance and more specifically a change of the whole substance into another substance as this was the meaning giving to the word by the theologians when it appeared in eucharistic theology.

How does it work?

As you say, to explain how metabolism works, one can’t just use the word ‘metabolism’ but needs to introduce other words and terms. Transubstantiation works by divine power and not according to the laws of nature and this is implicitly contained in the first sentence you quote from me.

What is going on beneath the surface?

Transubstantiation, i.e., a change of the whole substance of the bread into the substance of the body of Christ and the whole substance of the wine into the substance of the blood of Christ. The substance (from latin substare ‘to stand under’) is that which ‘stands under’ as it were the sensible ‘species’. ‘Species’ is a latin word which is translated ‘appearances.’ Species is the word the Church uses in its official terminology concerning what remains of the bread and wine after the change of the substances of the bread and wine. Species means the same thing as the ‘accidents’ in scholastic Aristotelian philosophical language. The change going on here at the substance level is metaphysical, i.e., beyond sense observation and sense phenomena unlike metabolism.

How do you know what you say is true?

Faith in the word of Jesus who is God and Truth itself as he himself declared ‘I am the Way, the Truth, and the Life.’ We believe that the bread and wine are transubstantiated into the true body and the true blood of Christ solely on the words of Jesus ‘This is my body…This is my blood’, the Bread of Life discourse in the gospel of John, and drawing an analogy between the figures in the Old Testament of the eucharist and the eucharistic sacrifice such as the sacrifice of the Passover Lamb, the Manna in the desert. We cannot prove by sense phenomena or sight that Jesus’ true body and true blood is in the eucharist ordinarily, I say ordinarily because there are a few eucharistic miracles in which blood or tissue is seen. Believing in the Real Presence of Christ’s true body and true blood in the eucharist which comes about by the transubstantiation of the bread and wine is an act of the virtue of faith which is meritorious.



The eucharist is one of the central mysteries of the catholic faith and we would no longer need to exercise our faith concerning Christ’s body and blood in the eucharist if we could see his body and blood there either with the naked eye or with the most powerful microscopes. The body and blood of Christ are substantially present under the appearances of the bread and wine but invisibly and beyond sense observation. The ‘science’ of how this precisely happens is known only to God and possibly whoever God may reveal it too in heaven.

Am I missing something here?

The two statements you quote from my post in reply to your query say something about transubstantiation but not everything. I was more or less replying to a specific question you asked. Just as the single word metabolism isn’t going to tell us much if anything about metabolism so the single word transubstantiation though quite meaningful in itself as it indicates a change of one substance into another substance doesn’t in itself tells us what substances we are talking about for example. So we need to add the words bread, wine, body and blood of Christ to explain what we are talking about. And if someone asks what is a substance, utilizing Aristotelian/Thomistic metaphysics we can provide an explanation as well as the distinction between substance and accident and Aristotle’s 10 categories of being, substantial changes and accidental changes, form and matter, potency and act, essence and existence or more properly termed the act-of-being, substantial forms and accidental forms, what is the essence of matter, what are the transcendental properties of being, what is being, etc. Indeed, a study of the whole Aristotelian/Thomistic metaphysics would be very valuable in trying to understand to some degree transubstantiation as explained by St Thomas Aquinas and the Catechism of the Council of Trent which catechism in general utilizes the Aristotelian/Thomistic metaphysics such as the distinction between substance and accident (cf. also USCCB website) and its utilization of the accident of quantity.

The Church in its official teaching concerning the dogma of transubstantiation does not employ the Aristotelian metaphysics as St Thomas did as useful as these metaphysics may be. For example, instead of ‘accidents’ the Church uses the term ‘species’ (appearances) in its official terminology. It seems the Church is wisely steering clear of making the foundation of our faith in the Real Presence of Jesus’ body and blood in the eucharist depend on any philosophical system, human reasoning, or science. Our faith in the Real Presence of Jesus is ultimately founded on the very words of Jesus alone and that faith handed on from the Apostles to the early Church down to the present day in Sacred Tradition. The word ‘transubstantiation’ which made its appearance in the eucharistic theology of the Church around the 11th-13th centuries is a more precise technical term and means the same thing as what the Fathers of the early Church said concerning a change in the nature, essence, reality or a transmutation of the elements of the bread and wine.


According to Rev. James T. O’Connor in his book titled ‘The Hidden Manna - A Theology of the Eucharist’ (this is an excellent book), the word transubstantiation made its appearance concerning eucharistic theology in the first half of the 12th century around 1140 A.D. Rolando Bandinelli, who became Pope Alexander III, was one of the first to use the term in a theological treatise which he wrote in 1140. The word also occurs in the works of two authors of around the same time but it is disputed whether these works may actually be the works of two other authors in the second half of the 12th century. By the time Lothar of Segni who became Pope Innocent III in 1198 wrote a work on the eucharist before he became the pope and using the word transubstantiation, Fr. O’Connor says that the word had become common by then. Transubstantiation is used in the Creed Firmiter of The Fourth Lateran Council (1215).

The use of the word ‘substance’ in eucharistic theology predates the word transubstantiation by quite a few centuries. For example, Paschasius Radbertus uses the term substance in a work concerning the eucharist around 833. I think a few earlier Church fathers may have employed the term as well but I can’t find the references at the moment. At any rate, as I mentioned in an earlier post, they use terms that essentially mean the same thing more or less as substance as when St Ambrose speaks of a change in the nature of the bread and wine (CCC#1375):
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.

In the Aristotelian/Thomistic terminology, to speak of the nature of some thing is to speak of the substance of the thing.


Thank you once again, @Richca, for taking the trouble to compose such an extensive and learned exposition in response to my naive questions. Since you mention Paschasius Radbertus, Willemien Otten has written a fascinating account of the Radbertus vs. Ratramnus confrontation. Otten is now at the University of Chicago but a few years ago, when she was still at the University of Utrecht in Holland, she published a paper in the Dutch Review of Church History tracing their arguments, on both sides, back to Augustine and Ambrose―she is an Augustine specialist, if I have understood correctly―and also addressing the interesting question of why the debate should have arisen when it did, in the 830s and 840s, and no earlier. Her answer, briefly, is that the wide-ranging ecclesiastical reforms initiated under Charlemagne (768-814) included the standardization of the liturgy throughout the Empire. This in turn triggered a new spirit of inquiry in the Church, particularly in Benedictine monasteries, which had “turned into citadels of learning in what was otherwise still largely a cultural wasteland. Apparently capable of nourishing a healthy diversity of opinion, scholars would not shy away from tackling prime theological matters.”


Actually, a Lutheran on Amazon’s now defunct discussions admitted Lutherans do believe in consubstantiation and believe they’re more Catholic than Catholics.


If he/she said they believe in consubstantiation, it is a matter of poor catechesis. Previously in this thread, and in other threads over my years here at CAF, I have posted a list of statements from the greatest theologians of the Lutheran tradition within the Church. All of them affirm a rejection of consubstantiation. Somehow, an anonymous poster on an internet site doesn’t hold the same weight


It is my belief that those who know what their church or denomination believes are members of the particular church. I’ve found that not all theologians are members of the religion they purport to have expertise in.

The Lutheran poster I am speaking of used her real name and not an alias. (Amazon had “badges” with “REAL NAME” for those courageous posters.) I was very surprised a few year later to find someone who was a convert to the Lutheran religion who also used his real name, disagreeing with the Lutheran who’d told me of their belief in it. (My question to the female Lutheran had been “Do Lutherans believe in consubstantiation?”) They were both members of the same Synod. So I don’t understand one saying they do believe in it and the convert saying they don’t.


There have been polls done of Catholics regarding the real presence.

Are Catholics who do not understand the Church 's teachings the ones who should be believed?


It’s curious that the breakdown of the “knowledgeable” and the “unknowing” should be exactly fifty-fifty. I wonder how no fewer than one-half of all American Catholics have managed to live their lives without ever having found out that their Church preaches the Real Presence.

That so many Catholics (37 percent) don’t believe it I can readily understand. That so many of them (50 percent) don’t know about it I find frankly puzzling.


St. Pope John Paul II commented on the belief of Catholics in an encyclical in 2003:

15. The sacramental re-presentation of Christ’s sacrifice, crowned by the resurrection, in the Mass involves a most special presence which – in the words of Paul VI –

“is called ‘real’ not as a way of excluding all other types of presence as if they were ‘not real’, but because it is a presence in the fullest sense: a substantial presence whereby Christ, the God-Man, is wholly and entirely present”.22

This sets forth once more the perennially valid teaching of the Council of Trent:

“the consecration of the bread and wine effects the change 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. And the holy Catholic Church has fittingly and properly called this change transubstantiation”.23

Truly the Eucharist is a mysterium fidei, a mystery which surpasses our understanding and can only be received in faith, as is often brought out in the catechesis of the Church Fathers regarding this divine sacrament:

“Do not see – Saint Cyril of Jerusalem exhorts – in the bread and wine merely natural elements, because the Lord has expressly said that they are his body and his blood: faith assures you of this, though your senses suggest otherwise”.24


Just like in my years of being Lutheran I thought puzzling that some Lutherans thought consubstantiation


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