15. Then God said to Abraham, “As for your wife, you must no longer call her Sarai; Sarah will be her name.
16. I will bless her and will give you a son through her. I will bless her and she will become a mother of nations. Kings of countries will come from her!”
17. Then Abraham bowed down with his face to the ground and laughed as he said to himself, “Can a son be born to a man who is a hundred years old? Can Sarah bear a child at the age of ninety?”
18. Abraham said to God, “O that Ishmael might live before you!”
19. God said, “No, Sarah your wife is going to bear you a son, and you will name him Isaac. I will confirm my covenant with him as a perpetual covenant for his descendants after him.