John Calvin Commentary Genesis 17:2

"And I will make my covenant between me and thee, and will multiply thee exceedingly." — Genesis 17:2 (ASV)

And I will make my covenant He now begins more fully and abundantly to explain what he had alluded to briefly before. We have said that the covenant of God with Abram had two parts. The first was a declaration of gratuitous love, to which was added the promise of a happy life.

But the other was an exhortation to the sincere effort to cultivate uprightness, since God had given only a slight taste of his grace in a single word; and then immediately had descended to the design of the call: namely, that Abram should be upright.

He now adds a fuller declaration of his grace, so that Abram might more willingly strive to shape his mind and life, both to reverence for God and to the cultivation of uprightness. It is as if God had said, ‘See how kindly I am gracious to you: for I do not require integrity from you simply on account of my authority, which I might justly do; but since I owe you nothing, I graciously condescend to enter into a mutual covenant.’

He does not, however, speak of this as something new; rather, he recalls the covenant which he had made before, and now fully confirms and establishes its certainty.

For God is not accustomed to speak new oracles that might destroy the credibility, obscure the light, or weaken the effectiveness of those that came before. Instead, he continues, with consistent continuity, those promises that he has once given.

Therefore, by these words, he intends nothing other than that the covenant of which Abram had heard before should be established and ratified; but he expressly introduces that main point concerning the multiplication of seed, which he later frequently repeats.