Genesis 17:19-21

Revised Standard Version

¹⁹ God said, “No, but Sarah your wife shall bear you a son, and you shall call his name Isaac.^[a] I will establish my covenant with him as an everlasing covenant for his descendants after him. ²⁰ As for Ish′mael, I have heard you; behold, I will bless him and make him fruitful and multiply him exceedingly; he shall be the father of twelve princes, and I will make him a great nation. ²¹ But I will establish my covenant with Isaac, whom Sarah shall bear to you at this season next year.”