Real presence in Eucharist


And this takes us back to faith. Who of us knows our essence? we believe it is spiritual. At the essential level we are changes by sacraments. While we try to rationalize (because we are rational beings) we only frustrate ourselves because essence, substance, or truest deepest identity are ideals.

Your example of the human person/soul takes us to baptism. Pour a little water say a few words. After wiping the water away there is no accidental difference. Faith alone tells us that we have a fundamentally changed individual.

Back to the Eucharist, defying logic we say it is no longer bread nor wine. It is purely a matter of faith.


An intuitive knowing.


Generally it is stated that the accidents inhere in the substance and the human soul which is a substantial form is united to the body made out of matter. Broadly speaking, you could probably say that the soul inheres to the body. I would not say that the body inheres to the soul because this would seem to suggest that matter of which the body is made out of is an entity in its own right. Matter is essentially a purely passive or receptive potentiality, it is completely formless, it does not exist without form and it is not an act as forms are. In this sense, something needs to come to it as it were to inform it such as what forms do. Forms inform and form matter. Forms are called the act of matter as matter is simply potency. The first act that the soul bestows on the matter of the body is existence, then it forms matter into a body and makes it a living body. This is conceived as according to the order of nature not as according to the order of time or duration.

True, it makes sense that the accidents of bread and wine don’t inhere in the body and blood of Christ as these are not accidents of a human body or human blood.

Yes, the human soul has a natural aptitude to be united to the body as a human being is substantially a composite of body and soul. Thus the souls who have died in Christ long for the resurrection of their bodies.


Yes, thank you. As a side not, the house-form is actually an accidental form (a work of art) not a substantial form because a house is an orderly arrangement or aggregate of various natural and already established substances such as wood and stone and probably man -made substances too. Yes, I agree, accidents reveal, indicate, point to the substance or essence.


Forgive me, for this is beyond my pay grade.

What about saying, accidents are what we can see and substance is what we cannot see.

What is the substance of Jesus Christ, for example?

We know what is bread or wine from what we see, or Jesus when was a human being. But we do not know how his divine form looks like much less his substance, which is really in essence, Him.

Can we say that in Transubstantiation, the substance of bread and wine is changed to the substance of Jesus Christ, which we partake in the Holy Communion?


We can say it, sure. Christ didn’t, however. He only said; “this is my body…”


Have we defined “substance”? That which stands under?

Is it an ideal as in our mental understanding of what a house is?

Or is it more “thingy” like our souls?


My substance (soul) which endures through the changing accidents of my body is very different from the substance (form) of a human being which is a mental ideal.

And yet I think we are using “substance” for each.


Richca, Thank you!


Read “Eucharistic Miracles” by Joan Carroll Cruz.

It will help a lot of direct your attention and focus further studies.


That is all we need to know, everything else is commentary.

We just need faith.


Putting the elements through a chemical lab will surely yield the result that they are bread and wine; why resort to Aristotelian niceties distinguishing the essential and the accidental in order to explain that result?

The results of a chemical lab test would reveal nothing but sense phenomena but the sense phenomena of the bread and wine do not change after the consecration of the bread and wine which is evident as seen with the naked eye. The essential principles of the substance of bread, for instance, in the Aristotelian hylemorphic structure of material reality and substance are beyond sense observation and can be only known by the intellect though indirectly through the accidents. So, in the Aristolelian hylemorphic structure of material reality and substance, an appeal to sense phenomena even under the most powerful microscopes cannot prove the presence of the substance although naturally the sense phenomena of a substance indicate, reveal, and manifest the presence of the substance and flow from the substance except in the case of the eucharist.

As far as the Aristotelian ‘niceties’ go, I think one needs to consider whether Aristotle’s philosophy and metaphysics and associated concepts conform to reality. Aristotle developed his philosophy and metaphysics by looking at the reality of the world around him and then proceeded to try and explain it in its essential and accidental principles. Any true philosophy and metaphysics needs to be grounded in reality that confronts us. We do not create reality, that was God’s job when he created the world, we discover it. The scholastic theologians, most notably St Thomas Aquinas, agreed more or less with the Aristotelian metaphysical structure of reality. And it just so happens that the Aristotelian concepts employed in their explanation of transubstantiation conforms with the Church’s faith concerning the Real Presence of Jesus’ body and blood in the eucharist and the wonderful and miraculous conversion of the bread and wine into his body and blood.


Yes, transubstantiation as the very word signifies means 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 of the body of Christ is his entire material body with all its parts and the substance of his blood is his material blood.


Your substance is not your soul alone but the composite of soul (form) and body (matter) and the soul is the form of the body. In the Aristotelian hylemorphic structure of material reality and material substance, form (the substantial form, there are also accidental forms) and prime matter are the substantial principles of material substance. Form and matter are real distinct entities in a material substance but they are said to be incomplete beings because that which primarily exists and is a being is the composite of form and matter, i.e., the substance. Matter without form does not exist at all.

The mental concept of humanity or man for, in stance, has an objective foundation in extra-mental reality, namely, individual human beings.

Substance can carry a number of meanings. Individual existing things such as individual humans, dogs, horses, trees, elemental atoms, are substances. This I believe is usually referred to as first or primary substance. Aristotle called second substance as the essence or nature of things. Substance also means that which exists itself and by itself and in this sense it is the subject of accidents which only exist in the substance. The english word ‘substance’ comes from the latin ‘substare’ (I believe this is the correct one) which literally means to ‘stand under’. Our english word ‘accident’ is also derived from a latin word (can’t think of it at the moment) which literally means ‘to fall on top of.’


Interesting post. Being that Adam named the animals and a name should correspond or indicate the nature of the thing, I would agree that Adam had a more perfect knowledge of the nature of things than we do and this is the opinion of St Thomas Aquinas too. I’m not sure if Aquinas says that some kind of preternatural power would have been required for this better ‘internal gaze’ into the natures of things. I don’t think I would agree that Adam and Eve had a power of direct communication with the angels and Aquinas does say that Adam did not know immaterial substances (direct knowledge of their natures) such as the angels as this is beyond the natural power of the human intellect.


Thank you. You know how much it means to me to hear someone saying this.


From all the replies, it seems clear that the body and blood of our Lord has many meanings. It seems that each one of us takes the meaning that we want to take from it.

It was a very hard teaching for the Jews who heard it, and many walked away from our Lord. It is still a challenging leap of faith to trust that we partake of the true body and blood of our Lord today.

We are in the week of Christian unity, and we pray that we may be ‘One’ as our Lord is ‘One’.



Aside from the definition that has been assigned to it by theologians in the context of the Eucharist, does the word “transubstantiation” have a more general meaning? Can the term legitimately be used, for instance, to designate what happens in a nuclear reactor when one element, uranium, gradually disappears while a different element, plutonium, is seen to take its place? Or in physiology, to denote the process whereby carbon dioxide is removed from the bloodstream and replaced by oxygen?

Is there any instance of transubstantiation, involving any materials, that is verifiable in a laboratory?


The Real Presence.

Maybe seven years ago, I attended a retreat preached by then 88 year old Fr. Antonius Wall, of the Western Dominican Province in the US. He addressed this exact point. He asked those gathered, “What did you eat for breakfast? Toast? Well then, what did your body do with that toast? It made your living flesh from it, without you giving it a thought. If our purely human bodies can do this, do we suppose that the Lord Himself cannot - especially when He said that is what He just did?” He went on, teaching that is what the Apostles believed and that is what we believe to this day.

Kinda stuck with me.


No. The use of the word transubstantiation arose in around the 11th or 12th century in relation to the eucharistic change of the bread and wine into the body and blood of Christ. 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. Consequently, transubstantiation can only be legitimately applied to the substantial and miraculous change concerning the eucharist. The prefix ‘trans’ come from the latin ‘trans’ or ‘tra’ and it means across, over, through, so as to change (Websters Collegiate Dictionary). Transubstantiation means a change of the whole substance, across or over the whole substance.

What is meant by the whole substance? Using Aristotelian/Thomistic philosophy and metaphysics, the whole substance involves the essential principles of material substances, namely, the substantial form and prime matter. In the world of nature, substantial changes involve a change of form (the substantial form as well as accidental forms) while the matter remains and so substantial changes in the world of nature are transformations. For example, the grass that a cow eats changes into cow flesh. The matter that was in the grass is the same matter that is in cow flesh but the form of the matter which we call grass changes to the form of cow flesh. Transubstantiation involves not just a change of the forms of bread and wine into the forms of the pre-existing body and blood of Christ but the matter too of the bread and wine into the matter of the pre-existing body and blood of Christ. And thus we have a change of the whole substance of the bread into the whole substance of the body of Christ and the whole substance of the wine into the whole substance of the blood of Christ. We are not familiar with this kind of change of the whole being of one thing into the whole being of something else because it doesn’t occur in our experience of the world by which we can compare it too or draw some sort of analogy.

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