to perform—those works that I myself perform—
they bear witness to me that the Father sent me.
37 Moreover, the Father who sent me has himself
given testimony on my behalf,
but you have neither heard his voice,
nor seen his image;
38 and you do not have his word abiding in your hearts,
for you do not believe in him whom he has sent.
39 Search the Scriptures,
since you think you have eternal life in them;
they too bear witness to me.
40 Yet you are unwilling to come to me
in order to possess that life.”
799 Having given us the teaching on the life-giving power of the Son, he now confirms it. First, he confirms, with several testimonies, what he had said about the excellence of his power. In the second place, he reproves them because of their slowness to believe (v 41). He does two things about the first. First, he states why there was a need to resort to such testimonies. Secondly, he invokes the testimonies (v 32).
800 The need to appeal to testimony arose because the Jews did not believe in him; for this reason he says: If I were to bear witness to myself, my testimony would not be valid ( verum , valid, true). Some may find this statement puzzling: for if our Lord says of himself, “I am the truth” (below 14:6), how can his testimony not be valid? If he is the truth, in whom shall one believe if the truth itself is not believed in? We may answer, according to Chrysostom, that our Lord is speaking here of himself from the point of view of the opinion of others, so that his meaning is: If I were to bear witness to myself, my testimony would not be valid so far as your outlook is concerned, because you do not accept what I say about myself unless it is confirmed by other testimony: “You are bearing witness to yourself; your testimony is not valid” (below 8:13).
801 Next, he presents these testimonies: first, a human testimony; secondly, a divine testimony. He does two things about the first. First, he mentions the testimony of John; secondly, he tells why this testimony was given (v 34). With respect to the first he does two things. First, he brings in the testimony; secondly, he commends it (v 32).
802 He brings on the witness when he says: But there is someone else who testifies on my behalf. This is, in the opinion of Chrysostom, John the Baptist, of whom we read above: “There was a man sent by God, whose name was John. He came as a witness, that he might bear witness to the light” (1:6).
803 He commends John’s testimony on two grounds: first, because of its truth; secondly, because of its authority, for the Jews had sought it (v 33).
804 He commends his testimony because of its truth, saying: And I know, from certain experience, that the witness he, that is, John, bears on my behalf is true. His father, Zechariah, had prophesied this of him: “You will go before the face of the Lord to prepare his way, to give his people a knowledge of salvation” (Lk 1:76). Now it is obvious that false testimony is not a testimony that saves, because lying is a cause of death: “A lying mouth kills the soul” (Wis 1:11). Therefore, if John’s testimony was for the purpose of giving knowledge of salvation to his people, his testimony is true.
805 The Gloss has a different explanation of this: If I were to bear witness to myself, my testimony would not be valid. For above, Christ was referring to himself as God, but here he is referring to himself as a man. And the meaning is: If I, namely, a man, were to bear witness to myself, i.e., apart from God, that is, which God the Father does not certify, then it follows that my testimony would not be valid, for human speech has no truth unless it is supported by God, according to: “God is true, but every man is a liar” (Rom 3:4). Thus, if we take Christ as a man separated from the Deity and not in conformity with it, we find a lie both in his essence and in his words: “Although I bear witness to myself, my testimony is true” (below 8:14); “I am not alone, because the Father is with me” (below 16:32). And so, because he was not alone but with the Father, his testimony is true.
Accordingly, to show that his testimony is true, not in virtue of his humanity considered in itself, but in so far as it is united to his divinity and to the Word of God, he says, But there is someone else who testifies on my behalf : not John, but the Father, according to this explanation. Because if the testimony of Christ as man is not of itself true and productive, much less is the testimony of John. Therefore, the testimony of Christ is not verified by the testimony of John, but by the testimony of the Father. So this someone else who testifies is understood to be the Father. And I know that the witness he bears on my behalf is true , for he is truth: “God is light,” i.e., truth, “and in him there is no darkness,” i.e., lie (1 Jn 1:5).
The first explanation, which is that given by Chrysostom, is nearer to the letter of the text.
806 He also commends the testimony of John by reason of its authority, because it was sought after by the Jews, saying: You sent [messengers] to John. As if to say: I know that his testimony is true and you should not reject it, because the great authority John enjoyed among you led you to seek his testimony about me; and you would not have done this if you did not think that he was worthy of belief: “The Jews sent priests and Levites from Jerusalem to him” (above 1:19). And on this occasion, John bore witness, not to himself, but to the truth , i.e., to me. As a friend of the truth, he bore testimony to the truth, which is Christ: “He declared openly, and did not deny, and stated clearly, ‘I am not the Messiah’” (above 1:20).
807 Then (v 34), he gives the reason why an appeal was made to the testimony of John. First, he excludes a supposed reason. Next, he presents the true reason (v 34b).
808 Someone might think that John’s testimony was brought in to assure them about Christ, on the ground that Christ’s own testimony was not sufficient. He excludes this reason when he says, I myself do not need proof from men . Here we should note that sometimes in the sciences a thing is proved by something else which is more evident to us, but which is less evident in itself; and at other times a thing is proved by something else which is more evident in itself and absolutely. Now, in this case, the issue is to prove that Christ is God. And, although the truth of Christ is, in itself and absolutely, more evident, yet it is proved by the testimony of John, which was better known to the Jews. So Christ, of himself, did not have any need of John’s testimony; and this is what he says: I myself do not need proof from men .