But since He said, “And the bread which I will give is My flesh,” and since flesh is moistened with blood, and blood is figuratively termed wine, we are bidden to know that, as bread, crumbled into a mixture of wine and water, seizes on the wine and leaves the watery portion, so also the flesh of Christ, the bread of heaven absorbs the blood; that is, those among men and into sympathy, in consequence of the nourishment which flows from the Word; and into immortality, through His guidance:
Clement of Alexandria
The Paedagogus, Book I
Chapter VI