Genesis 17:17-24

17Abraham fell facedown. Then he laughed and said to himself, “Can a child be born to a hundred-year-old man? Can Sarah, a ninety-year-old woman, give birth?”

18So Abraham said to God, “If only Ishmael were acceptable to you!”

19But God said, “No. Your wife Sarah will bear you a son, and you will name him Isaac. I will confirm my covenant with him as a permanent covenant for his future offspring.

20As for Ishmael, I have heard you. I will certainly bless him; I will make him fruitful and will multiply him greatly. He will father twelve tribal leaders, and I will make him into a great nation.

21But I will confirm my covenant with Isaac, whom Sarah will bear to you at this time next year.”

22When he finished talking with him, God withdrew from Abraham.

23So Abraham took his son Ishmael and those born in his household or purchased — every male among the members of Abraham’s household — and he circumcised the flesh of their foreskin on that very day, just as God had said to him.

24Abraham was ninety-nine years old when the flesh of his foreskin was circumcised,