I will make you exceedingly fruitful; and I will make nations of you, and kings shall come from you. I will establish my covenant between me and you, and your offspring after you throughout their generations, for an everlasting covenant, to be God to you and to your offspring after you. And I will give to you, and to your offspring after you, the land where you are now an alien, all the land of Canaan, for a perpetual holding; and I will be their God.
(Genesis 17:6–8)

These words, spoken by God, articulate God’s covenant, or promise, with Abraham. Initially in the Genesis narrative, the interaction between God and humans seems bewildering and arbitrary. God speaks to isolated individuals and demands certain actions from them. Here, God lays out a plan for an ongoing relationship with humankind. God will be the deity of one group of people, and the rights to God’s favor and blessings will pass on genetically from one man to his descendants. The rewards of this relationship will not only be a nation and a homeland for the Israelites but abundant, “fruitful” life. God’s comments here serve two functions. First, the passage introduces the dominant motif of the Old Testament: the covenant unifies the biblical narrative, for everything the Israelites do from this point on represents either an affirmation or a rejection of God’s promise. Second, the passage implies that the Israelites are not just any group or ethnicity, but a specific people descending from one man with a divine claim to land in the eastern Mediterranean region. Historically, the idea of the covenant was important for the Israelites in sustaining a sense of identity in the ethnic mix of the region as well as during the exile.