John Calvin Commentary John 7:29

"I know him; because I am from him, and he sent me." — John 7:29 (ASV)

But I know him. When he says that he knows God, he means that it is not without good reason that he has risen to such great confidence. By his example, he warns us not to invoke God's name lightly, so as to boast of Him as the patron and defender of our cause. For many are too presumptuous in boasting of God's authority; indeed, it is impossible to imagine greater readiness and boldness in rejecting everyone's opinions than is found among fanatics who present their own inventions as God's oracles. But these words of our Lord Jesus Christ teach us that we should especially beware of proud and foolish confidence, and that when we have fully ascertained God's truth, we should boldly resist men. And whoever is fully aware that God is on his side has no reason to fear being accused of insolence for trampling underfoot all the world's haughtiness.

Because I am from him, and he has sent me. Some distinguish these two clauses in this manner. They refer the first clause—I am from him—to the Divine essence of Christ; and the second clause—he has sent me—to the office entrusted to him by the Father, for the sake of carrying out which he took upon himself flesh and human nature. Though I do not venture to reject this view, I still do not know if Christ intended to speak so obscurely. I readily acknowledge that Christ’s heavenly descent may be inferred from it, but it would not be a sufficiently strong proof of his eternal Divinity against the Arians.