From Clement of Alexandria: “Paedagogus” (The Instructor).
“Eat ye my flesh,” He says, “and drink my blood.” Such is the suitable food which the Lord ministers, and He offers His flesh and pours forth His blood, and nothing is wanting for the children’s growth. O amazing mystery. We are enjoined to cast off the old and carnal corruption, as also the old nutriment, receiving in exchange another new regimen, that of Christ, receiving Him if we can, to hide Him within; and that, enshrining the Savior in our souls, we may correct the affections of our flesh.” (Paedagogus 1:6)
“But you are not inclined to understand it thus, but perchance more generally. Hear it also in the following way. The flesh figuratively represents to us the Holy Spirit; for the flesh was created by Him. The blood points out to us the Word, for as rich blood the Word has been infused into life; and the union of both is the Lord, the food of the babes–the Lord who is Spirit and Word. The food- that is, the Lord Jesus–that is, the Word of God, the Spirit made flesh, the heavenly flesh sanctified…” (ibid)
“But we are God-taught, and glory in the name of Christ. How then are we not to regard the apostle as attaching this sense to the milk of the babes? And if we who preside over the Churches are shepherds after the image of the good Shepherd, and you the sheep, are we not to regard the Lord as preserving consistency in the use of figurative speech, when He speaks also of the milk of the flock?… Elsewhere the Lord, in the Gospel according to John, brought this out by symbols, when He said: “Eat ye my flesh, and drink my blood; ” describing distinctly by metaphor the drinkable properties of faith and the promise, by means of which the Church, like a human being consisting of many members, is refreshed and grows, is welded together and compacted of both,–of faith, which is the body, and of hope, which is the soul; as also the Lord of flesh and blood. For in reality the blood of faith is hope, in which faith is held as by a vital principle.” (ibid)
“’I,’ says the Lord, ‘have meat to eat that ye know not of. My meat is to do the will of Him that sent Me.’ You see another kind of food which, similarly with milk, represents figuratively the will of God. Besides, also, the completion of His own passion He called catachrestically “a cup,” when He alone had to drink and drain it. Thus to Christ the fulfilling of His Father’s will was food; and to us infants, who drink the milk of the word of the heavens, Christ Himself is food. Hence seeking is called sucking; for to those babes that seek the Word, the Father’s breasts of love supply milk.” (ibid)
“Thus in many ways the Word is figuratively described, as meat, and flesh, and food, and bread, and blood, and milk. The Lord is all these, to give enjoyment to us who have believed on Him. Let no one then think it strange, when we say that the Lord’s blood is figuratively represented as milk. For is it not figuratively represented as wine? “Who washes,” it is said, “His garment in wine, His robe in the blood of the grape.” In His Own Spirit He says He will deck the body of the Word; as certainly by His own Spirit He will nourish those who hunger for the Word.” (ibid)
“For the blood of the grape–that is, the Word–desired to be mixed with water, as His blood is mingled with salvation. And the blood of the Lord is two fold. For there is the blood of His flesh, by which we are redeemed from corruption; and the spiritual, that by which we are anointed. And to drink the blood of Jesus, is to become partaker of the Lord’s immortality; the Spirit being the energetic principle of the Word, as blood is of flesh. Accordingly, as wine is blended with water, so is the Spirit with man. And the one, the mixture of wine and water, nourishes to faith; while the other, the Spirit, conducts to immortality. And the mixture of both–of the water and of the Word–is called eucharist, renowned and glorious grace; and they who by faith partake of it are sanctified both in body and soul. For the divine mixture, man, the Father’s will has mystically compounded by the Spirit and the Word. For, in truth, the spirit is joined to the soul, which is inspired by it; and the flesh, by reason of which the Word became flesh, to the Word.” (Paedagogus 2:2)