I in them, and thou in me. — These words are best regarded as a parenthesis more explicitly setting forth the thought of the union of the Father, the Son, and the believer. The thought is continued from the last verse, “That they may be one even as we are one: I in them, and Thou in Me, that they may be made perfect in one.” It is the thought which the words of Christ have uttered again and again, and which we yet feel that no words can utter. The disciples heard the words immediately after they had heard the allegory of the true vine (John 15); and the fullest meaning of separate words and phrases in these Chapter s is best arrived at by remembering that they were not uttered as separate words and phrases, but that they were spoken as a whole, and should be read as a whole; and that the most unfathomable of them were spoken in prayer from the Son to the Father.
That they may be made perfect in one. — Better,... unto one. The unity is the result of their being made perfect. (Comp. Notes on Hebrews 10:14 and 1 John 2:5; 1 John 4:12; 1 John 4:17-18.)
And that the world may know that thou hast sent me. — Better,... didst send Me. Comp. John 17:21. “That the world may know” (recognise) here is parallel to “that the world may believe,” in the earlier verse. We are to regard it, therefore, as another instance of the repeated expression of the fulness of thought; and this is borne out by the parallel in John 13:35; John 14:31. The thought which has been introduced here of the conviction of the unbelieving world, seems to be opposed to the context. The prayer is that the world, seeing in its midst the power which binds men together in unity, may believe and know that this is of God, who sent Christ into the world, and may accept for themselves the message of love which the “Sent of God” has brought unto them. (Comp. Note on John 3:16.)