Chapter V.
With the very words of the Lord, his body and blood are consecrated and truly made present; hence it can be well understood that this sacrament excels manna, the truth of which is confirmed by the word, Amen.
Do you want to know why it is consecrated with heavenly words? Receive the words. The priest says: 'Make this offering written, ratified, reasonable, acceptable, which is the figure of the body and blood of our Lord Jesus Christ. Who, on the day before he suffered, took bread into his holy hands, looked up to you, holy Father almighty, eternal God, giving thanks, he blessed it, broke it, and gave it to his apostles and disciples, saying: Take and eat all of you from this; for this is my body which will be broken for many.' (Luke 22:19).
Similarly, also, after supper, on the eve of his passion, he took the chalice, looked up to heaven to you, holy Father, almighty and eternal God, giving thanks, he blessed it, and gave it to his apostles and disciples, saying: Take and drink of this, all of you; for this is my blood. (Matt. XXVI, 27, 28). See all of that. Those words of the evangelist go up to 'Take', whether the body or the blood. Here are the words of Christ: Take, and drink from this all of you; for this is my blood. And see each one.
He took bread in his holy hands the day before he suffered. Before it is consecrated, it is bread; but when the words of Christ have been spoken, it becomes the body of Christ. Finally, listen to him saying: Take and eat of this all of you; for this is my body. And before the words of Christ, the cup is full of wine and water: when the words of Christ have been spoken, there the blood of Christ is made, which redeemed the people. Therefore, see how mighty is the word of Christ in converting all things. Then the Lord Jesus himself testifies to us that we should receive his body and blood. Should we doubt his faith and testimony?
Now return with me to my proposition. Great indeed and venerable is the fact that manna rained down from heaven for the Jews (Exod. XVI, 13): but understand. What is greater, manna from heaven or the body of Christ? Surely the body of Christ, who is the author of heaven. Furthermore, the manna that was eaten, died: whoever eats this body, will have forgiveness of sins and will not die eternally (De Consec., dist. 2, c. Ante, § Qui manduc.)
Therefore, you do not say in vain: Amen, now in spirit confessing that you receive the body of Christ. The priest says to you: The body of Christ; and you say: Amen, that is, true. Let the confession of the tongue be held by the heart.