What you behold now on the altar of God you saw there last night as well. But you have not yet heard what it is, what it means, and of how great a reality is the sacrament. What you see, then, is bread and a cup. This is what your eyes report to you. But your faith has need to be taught that the bread is the body of Christ, the cup the blood of Christ. Perhaps this rather brief statement might be sufficient for belief, but belief requires instruction, for the Prophet says: "Unless you believe, you will not understand" (Is 7:9). So now you can say to me: "You have taught us to believe. Explain, so we may understand."
For the following thought may arise in anyone's mind. "We know whence our Lord Jesus Christ took flesh, from the Virgin Mary. As an infant He was nursed. He was brought up. He grew. He attained manhood. He suffered persecution from the Jews. He has hanged on the wood, He was killed on the wood, He was taken down from the wood. He was buried. He rose on the third day. When He willed, He ascended into heaven; to there He lifted up His body. Thence will he come to judge the living and dead. Now He is there, enthroned at the right hand of the Father. How is the bread His body? And the cup, or what is in the cup, how is that His blood?"
These things, my brothers, are called sacraments for the reason that in them one thing is seen, but another is understood. That which is seen has physical appearance, that which is understood has spiritual fruit. If, then, you wish to understand the body of Christ, listen to the Apostle as he says to the faithful "You are the body of Christ, and His members" (1 Cor 12:27). If, therefore, you are the body of Christ and His members, your mystery has been placed on the Lord's table, you receive your mystery. You reply "Amen" to that which you are, and by replying you consent. For you hear "The Body of Christ," and you reply "Amen." Be a member of the body of Christ so that your "Amen" may be true.
But why in bread? I provide nothing of my own at this point, rather let us listen together to the Apostle who said, when he was speaking about this sacrament, "We, though many, are one bread, one body" (1 Cor 10:17). Understand and rejoice. Unity! Verity! Piety! Charity! "One bread." What is this one bread? "Many... one body." Remember that bread is not made from one grain, but from many. When you were exorcised you were, after a fashion, milled. When you were baptized you were moistened. When you received the fire of the Holy Spirit you were baked. Be what you see, and receive what you are. That is what the Apostle said about the bread, and he has already indicated quite well what we are to understand of the cup, even though he did not say it. For just as in the preparation of the bread which you see, many grains were moistened into a unity, as if there were taking place what Holy Scripture says about the faithful, "They had one mind, one heart toward God" (Act 4:32), so also in the case of the wine. Brothers, recall whence wine comes. Many grapes hang in the cluster, but the liquid of the grapes is mixed in unity. So also did Christ the Lord portray us. He willed that we belong to Him. He consecrated the mystery of our peace and unity upon His table. He who receives the mystery of unity and does not hold fast to the bond of peace, receives not a mystery for himself, but testimony against himself.
Turning toward the Lord God, the Almighty Father, with a pure heart, let us render great and true thanks to Him, as much as our incapacity can. With all our soul, let us beg His singular gentleness that He may deign to hear our prayers with favor, that He may also drive the enemy from our actions and thoughts by His power, that He may increase our faith, guide our minds, grant us a spiritual way of thinking, and bring us to His blessedness, through Jesus Christ His Son. Amen.