Chapter 18 — Part II: The Sacraments — The Holy Eucharist
Section 99. In St. John Christ the Lord also says: The bread that I will give is my flesh, for the life of the world. The bread which He promises to give, He here declares to be His flesh. A little after He adds: Unless you eat the flesh of the son of man, and drink his blood, you shall not have life in you. And again: My flesh is meat indeed, and my blood is drink indeed. Since, therefore, in terms so clear and so explicit, He calls His flesh bread and meat indeed, and His blood drink indeed, He gives us sufficiently to understand that none of the substance of the bread and wine remains in the Sacrament.