Gen. 17 is both rich and complex, and pushes the story forward. Here for the first time we have the institution of required circumcision on the eighth day in connection with the covenant, and the connection is even verbal ‘karath berit’ is literally to cut a covenant, and the same verb is used to refer to the cutting off of the foreskin. As Alter says, while there were some ANE cultures that practiced circumcision this was usually in connection with puberty, not birth, and in Egypt it was a special rite for priests. So the Hebrew ritual was distinctive. What is especially interesting about this rite is that it was to be practiced on every male that was part of the kin group, including all the slaves, which would indicate they were part of the covenant community. My old teacher Meredith Kline did a lot of research on this rite, and since there is a line in this text about ‘if you don’t keep the covenant, then you will be ‘cut off’, he is probably correct that this covenant sign was a reminder that God could cut off his people if they disobeyed, indeed cut them off from the promise of descendants. In other words, circumcision, while an initiatory rite was a reminder of the oath curse— disobey the commandments and God will cut you off from the promised blessings.
This particular epiphany of God to Abram is also the point where we get the name change from Abram to Abraham, but Alter says there is not much difference in meaning in the two, unlike the case with Sarai and Sarah. Abraham means something like exalted father since Ab is the Hebrew word for father, and Sarah means princess. And while we are dealing with names, while we know that El is the generic name for God, we are not at all sure what Shaddai means. One popular conjecture is that it means mountain. Comparing Exod. 6.3 all we know for sure is that it is an archaic name for God, used before we get to the personal name of Yahweh which is revealed much later to Moses.
When God once again tells Abram that he will multiply his kindred, and Abram is now almost 100, Abram throws himself on the ground on his face and the reason for the name change is that God now says Abram will be the father of many nations, not just many offspring. God even says kings will come forth from Abram’s descendants. The covenant is not just with Abram, but also with his descendants, and there is even a promise of kings coming forth from his descendants, i.e. rulers of nations, so at this point there is a political dimension to the promise. And here we have the clear promise ‘and I will give you the whole land of Canaan ‘as an everlasting holding’, which is no doubt a promise ultra-orthodox Jews are holding God to, as they try to reclaim the whole land from Palestinians.
The commandment in particular Abram is to keep right away is the command to circumcise all the males, including Abram himself ‘My covenant in your flesh shall be an everlasting covenant’. It is thus not first with the Mosaic covenant that this commandment is instituted, but notice we do not have a sabbath commandment connected with the Abrahamic covenant, nor a bunch of Levitical food laws either.
Sarah also gets a name change at this juncture, and God is explicit in saying that SHE will bear Abraham a son whose name shall be Yitshaq. This is indeed the Hebrew word for ‘laughed’ and it will later be connected with Sarah laughing at the idea of being able to bear a child long past menopause. But here at vs. 17 Abraham again throws himself on his face and laughs at the notion he will be a father through Sarah. He would be content if Ishmael would be the favored son of Abraham through whom many offspring will come, and God promises that he also will be the progenitor of twelve tribal chiefs and of a great nation, just not the chosen line of God’s people. Notice that in this chapter the promises don’t have to do with salvation in the later Christian sense of the term. They have to do with offspring, and in the case of Abraham, also a promise of a land in which God’s people can live. The concept of election here, and later has to do with God’s historical purposes for his chosen people to be a light to the nations and a blessing to the world. It does not have to do with personal or individual salvation. In the NT as well, Christ is the seed of Abraham according to Paul, and the Elect or Chosen One of God, chosen before the foundation of creation by God to be the savior of the world. Now Jesus himself, not being a sinner, did not need to be saved, and so it is perfectly clear from his unique case that election is one thing, and salvation is another. These two ideas should not be merged into one idea such that elect=saved. Later proof of this fact comes in the case of Cyrus the Persian who is the only one called Mashiach in the OT– God’s anointed one who would free the Jewish exiles. This says nothing about Cyrus’ personal salvation.
Nevertheless, despite his skepticism and laughter, Abraham does exactly as God says, and has all the males circumcised, including Ishmael who by then was 13. There is at the end of the chapter a brief references to slaves bought with silver, presumably silver weights, because this is before the age of coin making.