7 Following the imperative, the cohortative indicates consequence. If Abram is blameless, then the Lord will ratify the covenant. Earlier the Lord ratified part of his promise to Abram (see Gen 15:18–21), guaranteeing him that his descendants would live in the land. But the expanded form of the promise, which includes numerous descendants and eternal possession of the land, remains to be ratified. This expanded form of the promise is in view here (see vv. 2b, 4–8). See the note at and R. B. Chisholm, “Evidence from Genesis,” A Case for Premillennialism, 35–54.
8 Heb “I will multiply you exceedingly, exceedingly.” The repetition is emphatic.
9 Heb “And Abram fell on his face.” This expression probably means that Abram sank to his knees and put his forehead to the ground, although it is possible that he completely prostrated himself. In either case the posture indicates humility and reverence.
10 Heb “God spoke to him, saying.” This is redundant in contemporary English and has been simplified in the translation for stylistic reasons.

In other versions

that I may make my covenant between me and you, and may multiply you greatly.” Then Abram fell on his face. And God said to him,

Then I will make my covenant between me and you and will greatly increase your numbers.”

Abram fell facedown, and God said to him,

I will set up my covenant between me and you, and I will multiply you greatly.”

Then Abram fell facedown and God spoke with him:

I will make a covenant with you, by which I will guarantee to give you countless descendants.”

At this, Abram fell face down on the ground. Then God said to him,

so that I may make my covenant between me and you, and may multiply you exceedingly.” Then Abram fell upon his face and God spoke with him, saying,

And I will make my covenant between me and thee, and will multiply thee exceedingly. And Abram fell on his face: and God talked with him, saying,

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