John 17:7

He proceeds to say, "And they have kept Thy word: now they have known that all things, whatsoever Thou hast given me, are of Thee;" that is, they have known that I am of Thee. For the Father gave all things at the very time when He begat Him who was to have all things. "For I have given unto them," He says, "the words which Thou gavest me; and they have received them;" that is, they have understood and kept hold of them. For the word is received when it is perceived by the mind. "And they have known truly," He adds, "that I came out from Thee, and they have believed that Thou didst send me." In this last clause we must also supply "truly;" for when He said, "They have known truly," He intended its explanation by adding, "and they have believed." That, therefore, "they have believed truly" which "they have known truly;" just as "I came out from Thee" is the same as "Thou didst send me." When, therefore, He said, "They have known truly," lest any might suppose that such a knowledge was already acquired by sight, and not by faith, He subjoined the explanation, "And they have believed," so that we should supply "truly," and understand the saying, "They have known truly," as equivalent to "They have believed truly:" not in the way which He intimated shortly before, when He said, "Do ye now believe? The hour cometh, and is now come, that ye shall be scattered, every man to his own, and shall leave me alone." But "they have believed truly," that is, in the way it ought to be believed, without constraint, with firmness, constancy, and fortitude: no longer now to go to their own, and leave Christ alone. […]

"And they have kept Thy word." "Now they have known that all things whatsoever Thou hast given Me are of Thee." How did they "keep Thy word"? "By believing in Me, and giving no heed to the Jews. For he that believeth in Him, it saith, 'hath set to his seal that God is true.'" (c. iii. 33.) Some read, "Now I know that all things whatsoever Thou hast given Me are of Thee." But this would have no reason; for how would the Son be ignorant of the things of the Father? No the words are spoken of the disciples. "From the time," He saith, "that I told them these things, they have learnt that all that Thou hast given Me is from Thee; nothing is alien, nothing peculiar to Me, with Thee." "They therefore have known that all things, whatsoever I teach, are Thy doctrines and teachings." "And whence have they learnt it?" From My words; for so have I taught them. And not only this have I taught them, but also that "I came out from Thee." For this He was anxious to prove through all the Gospel.

And now they have known that all things which you have given me are from you, and therefore they have known you by knowing me: whence above in the fifth chapter: "The Son cannot do anything of himself"; above in the fourteenth chapter: "The Father …

He takes our infirmities without himself being infirm and hungers without hungering. He sends up what is ours that is may be abolished. As he does this, in the same way, the gifts that come from God instead of our infirmities he also receives so …

And they have kept Thy word. He calls Himself the Word of the Father, because the Father by Him created all things, and because He contains in Himself all words: as if to say, They have committed Me to memory so well, that they never will forget Me. Or, They have kept Thy word, i. e. in that they have believed in Me: as it follows, Now they have known that all things whatsoever Thou hast given Me, are of Thee. Some read, Now I have known, &c. But this cannot be correct. For how could the Son be ignorant of what was the Father's? It is the disciples He is speaking of; as if to say, They have learnt that there is nothing in Me alien from Thee, and that whatever I teach cometh from Thee.