Why do Catholics believe that Bread and Wine Actually change in substance, that is, that they are no longer Bread and Wine?
It seems you can believe in the Real Presences with out the Bread and Wine actually changing into some other substance.


I won’t give a highly detailed answer; there are others who can do that. I guess the first thing that comes to my mind though, is the words of institution. Jesus holds the bread and the wine and says “This IS my body… This IS my blood.” It seems to me to infer a complete change of substance, not an admixture of Jeus with bead or wine.


I think the most straightforward answer is that Catholicism believes this because this is the understanding that was taught to the Apostles. We believe it because they believed it, and they believed it because it was revealed to them by God.

The scriptures certainly support this belief. “This is my body” is pretty clear. No matter what it seems to be, what it is is the body of Christ - nothing more, nothing less. Same with “this is my blood”.

BTW it’s not only Catholics who believe this, but Eastern Orthodox as well, along with others. Those Christians who do not believe it are actually a small minority of all Christians.


I could be wrong; but I think the EO believe it remains Bread and Wine, and yet there is still a real presents.


No, I’m quite certain that they believe that the Eucharist is no longer bread and wine. At least, that’s what I’ve heard from every EO who I have heard address the question. But they’re reluctant to use the term “transubstantiation”, preferring to refer to it simply as a mystery - not that the two are at odds. :slight_smile:

Again, the text is clear. “IS”, not “contains” or “encompasses”.


Trans… suggest that the Bread is no longer Bread I don’t think they hold to that. it is a mystery to them because it IS the Body and it IS Bread, same for the Wine.
I don’t think they get into How it is they just say it is. Trans… is an attempt to get into the How.


How do you define “substance”?



I guess you would have to ask the Orthodox about that. But be aware that they tend to leave the nature of Christ’s Eucharistic presence in the realm of inscrutible mystery, and do not attempt to explain it.

In the West, intellectual history took a different turn. Theology, considered “the queen of sciences,” became very much intertwined with the exercise of reason. The definition of transubstantiation was an attempt to understand God’s sacramental action. While transubstantiatiion attempts to describe WHAT happens in the Eucharist, it does not explain HOW it happens – other than to attribute the transformation to the power of the Holy Spirit.

The key word in thinking about Transubstantiation is not “is” but rather “this.” What is “this” that IS “my Body?” It is the substance [underlying identity or “thingness”] of what the Lord (or the Priest) is holding in his hand. So the attributes of “breadness” and “wineness” are not changed but the ontological essence is changed.

(Is that a tautology?)


Wouldn’t a dual nature theory be a better way of explaning it. It would also tie in well with the incarnation.


Dual nature? I don’t understand.


for example Christ is both Human and Divine


Hmmm. Interesting thought. I’ll have to scratch my head about it for a while.

You seem to be driving towards a Lutheran understanding of the Real Presence. They believe (watch me get this wrong) the He is present WITH the elements but that they do not change. They [at least the mainstream ones] also believe that when the service is over the Lord leaves the elements. Some have a more Catholic reverence for the elements, but my local Lutheran church tosses the bread to the birds.


But Christ did not become bread and wine as he became man. Rather, bread and wine become Christ. Not the same thing at all.

I don’t think anybody teaches that in heaven Christ is true bread and wine, but in heaven he is true man (as well as true God, of course).

I think it would also be very problematic for Christ to have incorporated two (three, actually) different and incompatible material natures. Human, bread and wine?


This is why…The Eucharist IS Scriptural

Let’s see if you read it.


JTBT is a good citizen. She’ll read it.


Maybe I am closer to the Lutherens I don’t know exactly what they believe, my own tradition says they are only symbols I tend to believe they are more so, I’m working from the assumption that some version of real presence is true.
I’m not trying to argue only to have a discussion here so take it easy.


Some of the apostles, particularly John and Mathew were involved in writing their Gospels, if not directly, at least indirectly. John 6 teaches “This IS my body” "This IS my blood.

St. Paul teaches this in one of his epistles. The very early writers, called The Church Fathers taught this. As centuries passed, it has been taught in every age. In about the 11th Century St. Thomas, using the meta-physics of Aristotle explained the Mystery that had been taught for at least a millenium and called the change of bread and wine into the body and blood of Jesus Christ transsubstantiation; a new word trying to explain, what had been held as fact for centuries and which has continued to be held by the Catholic and Orthodox Churches to this very day.

A lot of our modern doubt occurs because the notion of substance in modern science is quite different from the notion of substance in the meta-physics of St. Thomas. I am no great shakes as a meta-physician so perhaps someone else can go from here. :slight_smile:



Remember the accidents of the bread and wine remain (they still appear, taste, etc. as bread and wine).

It is the substance that changes.

As others have said, it is a great mystery. We just have to trust Christ and the Apostles on this one.

It often amazes me, though, that “Bible Christians” who preach literal interpretation of the Bible choose not to take Christ litreally when He says “this is my body”.

God Bless


exactly!!! that is where I’m going, why do RC’s still use this word? why not drop it and start using the term Real Presence again?


see my response to rwoehmke, St. Thomas is the one who started trying to explain it using accidents etc.

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