Tractates on the Gospel of John

⁵ But since, on the ground that the Mediator between God and men, the man Christ Jesus, has become Head of the Church, they are His members; therefore He says in the words that follow, “And for their sakes I sanctify myself.” For what means He by the words, “And for their sakes I sanctify myself,” but I sanctify them in myself, since they also are [part of] myself? For those of whom He so speaks are, as I have said, His members; and the head and body are one Christ, as the apostle teaches when he says of the seed of Abraham, “And if you be Christ's, then are you Abraham's seed,” after having said before, “He says not, And to seeds, as in many, but as in one, And to your seed, which is Christ.” If, then, the seed of Abraham is Christ, what else is declared to those to whom he says, “Then are you Abraham's seed,” but then are you Christ?

Of the same character is what this very apostle said in another place: “Now I rejoice in my sufferings for you, and fill up that which is lacking of the afflictions of Christ in my flesh.” He said not, of my afflictions, but “of Christ's;” for he was a member of Christ, and in his persecutions, such as it behooved Christ to suffer in the whole of His body, he also was filling up his own share of His afflictions. And to be assured of the certainty of this in the present passage, give heed to what follows.

For after saying, “And for their sakes I sanctify myself,” to let us understand that He thereby meant that He would sanctify them in Himself, He immediately added, “That they also may be sanctified in the truth.” And what else is this but in me, in accordance with the fact that the truth is that Word in the beginning which is God? In whom also the Son of man was Himself sanctified from the beginning of His creation, when the Word was made flesh, for the Word and the man became one person.

Then accordingly He sanctified Himself in Himself, that is, Himself the man in Himself the Word; for the Word and the man is one Christ, who sanctifies the manhood in the Word. But in behalf of His members He says, “And for their sakes I,”— that is, that the benefit may be also theirs, for they too are [included in the] I, just as it benefited me in myself, because I am man apart from them— “I sanctify myself,” that is, I sanctify them as if it were my own self in me, since in me they also are I.

“That they also may be sanctified in the truth.” For what else mean the words “they also,” but [“they”] in the same way as I; “in the truth,” and that “truth” am I? After this He now begins to speak not only of the apostles, but also of the rest of His members, which we shall treat of, as grace may be granted us, in another discourse.