John Chrysostom

Wherefore that He establishes no more, for they had heard it sufficiently, but he speaks of the cause of His passion, namely, the taking away of sins. And He calls it blood of a New Testament, that of the undertaking, the promise, the new law. For this He undertook also of old, and this comprises the Testament that is in the new law. And like as the Old Testament had sheep and bullocks, so this has the Lord's blood. …

Homily on the Gospel of Matthew 82 ↗

Jerome

But I say to you, I will not drink from this fruit of the vine from now on until that day when I drink it new with you in my Father's kingdom. He transitions from the physical to the spiritual, citing that the vineyard transplanted from Egypt is the people of Israel, to whom the Lord speaks through Jeremiah: I planted you a true vine, but how you have turned into the bitter fruit of a foreign vine (Jeremiah 2:21). And the prophet Isaiah sings in a song to his beloved, and the entire Scripture testifies accordingly. …

Commentary on Matthew ↗

Thomas Aquinas

For this is my blood etc. These are the words of consecration. And note that in these words there is a difference from those which the Church uses. The Church adds: this is the chalice. Likewise, where he says of the new testament, the Church adds of the new and eternal testament. Likewise, where he says which shall be shed for many, the Church adds which shall be shed for you etc. Whence then does the Church have this form? …

Commentary on Matthew ↗

Bonaventure

In the Sacrament of the Eucharist the true body and true blood of Christ is not only signified, but also truly contained under a twofold species, namely of bread and wine, as under one, not under a twofold Sacrament: and this is after the priestly consecration, which takes place in the utterance of the vocal form instituted by the Lord; over the bread, namely: This is my body; and over the wine: This is the chalice of my blood. …

Breviloquium, Part 6 ↗