At What Moment does Transubsantiation Occur?

At what precise moment should I cease to look at what is on the altar as bread/wine and rather as the body/blood of Christ?

Is it when the priest makes the sign of the cross over the gifts, “this is my body/blood”, or at the elevation? or something else entirely?

This has become an area of contention in the last few years, especially since in one Eastern rite, there are no words of institution which makes things valid. Let’s just say the entire canon or EP needs to be said.

As St. Thomas Aquinas says (Summa Theologica III, question 75), the consecration of the bread is effected by the words “This is my Body”, and the consecration of the wine is effected by the words “This is the chalice of my Blood”. The bread is transubstantiated once the proper words have been spoken by the priest, and the wine is transubstantiated the moment its own proper words have been completed. The Elevation would not be the moment of transubstantiation, nor could it happen at all if the gifts were not already consecrated, for that would be idolatry of bread and wine.

Eastern Catholics believe that the fullness of the consecration is not finished until after the Institution Narrative is done, when the priest and all the people ask the Holy Spirit to consecrated the bread and wine. They see it as a process, not an “instantaneous moment”. Different theology.

Without getting even more specific, when the priest pronounces the words “this is My Body” the bread becomes the Body of Christ. Before that moment, it is just bread.

Same for the wine/Blood.

I’ve always believed it happens between of the calling down of the Holy Spirit to make these gifts holy (when the 1st bell is rung) and the end of the words of institution (when the last bell is rung in the Canon).

However I was taught that it happened between the Sanctus and the Great Amen. And it was left at that.

I have trouble believing it happens twice; once for bread and once for wine. But my belief does not make it happen or not happen, that is left to the HS.

Actually I thought it was in the breaking of the bread right before it is lifted up as the sacrificial offering (as Jesus on the cross was lifted up) and we have lifted up our hearts to Him. That’s when the apostles saw Jesus on the road to Emmaus.

Luke 24:35 Then the two told what had happened on the way, and how Jesus was recognized by them when he broke the bread.

That is what I was taught for years, decades. I don’t quite understand why there is such confusion now, except possibly for the Eastern liturgies. The priest acts in persona Christi, so it would seem to me that when he does what Christ did, speaking the words of consecration, that is when the consecration occurs.

Oh my apologies Father, I did not see you were a priest. So you know best!

It leads me to the question, does the priest break the host while he says the words this is my body? Because I notice when the priest lifts up the body of Christ it is already broken but held together.

The Churches of both West (Catholic) and East have different but complimentary versions. The moment of Consecration in the Catholic Mass must occur when the Priest offers those same words as did Jesus. This is the time when the Holy Spirit under instructions from the Heavenly Father does His thing by changing the species of bread and wine into the Resurrected Jesus Christ. All of what the priest does within the authority given to him is to offer the prayer and words so as to effect the change. The change is always done by God. Since there is hardly any mention of the operation of the Holy Spirit in effecting the change in the Catholic Mass, the Catholic Church would mention that the change occurs precisely when the priest elevates both bread and wine. The Holy Spirit oddly is only mentioned at a certain time at the Consecration prayer. The Eastern Churches put more emphasis on the operation of the Holy Spirit to effect the change and in their Consecration prayers the Holy Spirit is even asked to come down from the Father to do His Work. Listen to the prayers which is contained in the Eastern Orthodox Divine Liturgy which is the same as the Catholic Mass.

At the Altar the Sub-Deacons and Altar Servers all prostrate before the Holy Gifts as they prepare for the coming of the Holy Spirit.

Priest: Again we offer unto thee this reasonable and unbloody service, and beseech thee and pray thee and supplicate thee: send down the Holy Spirit upon us and upon these Gifts here spread forth:

(The Priest signs the Holy Bread with the sign of the Cross saying:)

And make this bread the Precious Body of thy Christ;
People: Amen!

(The Priest makes the sign of the Cross over the Chalice saying:)

And that which is in the cup, the most Precious Blood of thy Christ;
People: Amen!

(The Priest makes the sign of the Cross over both the Holy Gifts saying:)
Changing them by the Holy Spirit: (Here everyone says) Amen, Amen, Amen!

Now the priests and Deacons join with the rest to prostrate before the Holy Gifts which are now have become the living Resurrected Lord Jesus Christ. They spend some moments in this act of adoration.

Here you can see where the Eastern Orthodox Church places the moment of Consecration at. In both Churches while the Eastern Churches describes precisely the role of which the Holy Spirit makes it is the same as it contained within the Catholic Mass. The whole of the Trinity is at work to give us this salvation this work of their love.

No. The Church knows best. :slight_smile:

This really is a settled question.

I’m just passing along what the Church has already decided.

That’s not to attempt to stifle any discussion; but to clarify that it is not what I write here that matters, but what the Church teaches.

The Eastern Churches have their own theology. I respect that (and wholeheartedly agree), but at the same time, leave it for the Eastern Churches forum.

No. St John Paul the Great went so far as to define that as a grave abuse.

The consecrated Host is broken during the Lamb of God. When the priest elevates It while saying “Behold the Lamb of God…” at that point, It was already broken. Perhaps you’re thinking about that time instead?

The prayers are just different. In the Byzantine Rite, the epeclesis comes after the words of institution. It would not make any sense at all to say that consecration has occurred at the words of institution, when a minute or two later, we pray to the Holy Spirit to come up on the gifts and change them. I know that there isn’t an explicit epeclesis in the Roman Canon, but in all the more recent Eucharist prayers, the epeclesis comes before the words of institution, so it would make sense that the words of institution complete the action and effect the consecration.

As far as leaving it to the Eastern Churches forum, I think that we can all benefit from understanding how churches other than our own understand the truths of the faith, in order to clarify the understanding of our own traditions. We shouldn’t be relegated to the Eastern forum alone in order to express our understanding.

Thank you Father now I don’t know, I’m confused looking for the order of the mass… I’ll have to pay better attention…

Edits: now I do recall seeing the priest break the bread while praying the “Lamb of God…” and this would be after the consecration…

Oh I am loving this!

Early in my catechesis, this question was asked. Our dear priest, after giving the answer in much the same way folks have in this thread, asked that we remember that the Eucharist is a Mystery, and to try not to focus on the ‘mechanics’. The nous should be open to God at that moment, he would say.

I read a book on the Eucharist by Fr. Alexander Schmemann in which he said, “The sacraments do not make things to be what they are not – it reveals them to be what they truly are.”

Interesting. Thanks for answering my question. It’s something I’d been wondering about.

I would love to see some authoritative document stating this as fact rather than opinion. This would imply that transubstantiation occurs twice during mass and that the word’s are magic words.

I believe that many people hold this view, but I do not believe the Church teaches this authoritatively.

I suppose one might ask at what point transubstantiation took place during the Last Supper, since the priest, acting In Persona Christi repeats Jesus’ words at Mass, as a sacramental means of making present the same sacrifice.

Probably one should not try to get too technical. Here is a quote from the catechism which might apply.

1412 The essential signs of the Eucharistic sacrament are wheat bread and grape wine, on which the blessing of the Holy Spirit is invoked and the priest pronounces the words of consecration spoken by Jesus during the Last Supper: “This is my body which will be given up for you. . . This is the cup of my blood. . . .”

1413 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 his Blood, with his soul and his divinity (cf. Council of Trent: DS 1640; 1651).

From the Catechism:
1377 The Eucharistic presence of Christ begins at the moment of the consecration and endures as long as the Eucharistic species subsist. Christ is present whole and entire in each of the species and whole and entire in each of their parts, in such a way that the breaking of the bread does not divide Christ.207

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