So far, God has clearly communicated his election of Abram. In his very first words to Abram, Yahweh declared his intentions to make Abram into a great nation, to bless him, and to make his name great in order for Abram to be a blessing to the world, so that in Abram all the families of the earth will be blessed (Gen. 12:2–3). How exactly, though, do the blessings of Yahweh’s gracious calling and election of Abram extend to all the families of the earth? What rightful claim to these blessings does anyone other than Abram have to the blessings that Yahweh promised to Abram?

In some ways, this is the nagging question behind the sin of Abram and Sarai with Hagar. Sarai recognized that Yahweh had promised to give biological offspring to Abram (Gen. 15:4), but she did not understand that she must personally conceive that offspring (Gen. 16:2). Even Hagar fled from the house of Abram because she did not understand her own new connection to Abram’s promises until Yahweh clarified his intentions to include her and Ishmael in some of the blessings reserved for Abram (Gen. 16:10–12). Moving forward, one of the key questions that Yahweh must clarify for everyone in the world is this: How do I know whether the promises for Abram in any way extend to me? Indeed, after his grievous sin with Hagar, even Abram may be wondering whether he still has a rightful claim to Yahweh’s promises.

For this reason, Yahweh now ratifies the covenant that he made with Abram in Genesis 15. That is, Yahweh confirms and authenticates not only the trustworthiness of his promises, but also the rightfulness of his people’s claim to those promises. By the end of Genesis 17, Yahweh will have clarified the difference between those who have a rightful claim to his covenant promises, and those who do not. To make this difference clear, Yahweh now gives a covenant sign as the ratification of his covenant promises. That is, all those who possess the sign of the covenant know that they may rightfully lay hold of the blessings of the covenant. Or, put another way: God gives covenant signs to ratify our claim to his covenant promises.