Christ on a certain occasion discoursing with the Jews said, Except ye eat My flesh and drink My blood, you have no life in you. They not having heard His saying in a spiritual sense were offended, and went back, supposing that He was inviting them to eat flesh.

In the Old Testament also there was show-bread; but this, as it belonged to the Old Testament, has come to an end; but in the New Testament there is Bread of heaven, and a Cup of salvation, sanctifying soul and body; for as the Bread corresponds to our body, so is the Word appropriate to our soul. — Catechetical Lecture 22.