Augustine of Hippo

For the flesh does not cleanse of itself, but by the Word who assumed it: which Word, being the principle of life in all things, having taken up soul and body, cleanseth the souls and bodies of those that believe. It is the spirit, then, that quickeneth: the flesh profiteth nothing; i. e. the flesh as they understood it. I do not, He seems to say, give My body to be eaten in this sense. He ought not to think of the flesh carnally: The words that I speak unto you, they are spirit, and they are life.