Genesis 17:15-19

15Then God said to Abraham, “As for Sarai your wife, you shall not call her name Sarai, but 1Sarah shall be her name.

16I will bless her, and indeed I will give you 2a son by her. Then I will bless her, and she shall be a mother of nations; 3kings of peoples will 4come from her.”

17Then Abraham 5fell on his face and laughed, and said in his heart, “Will a child be born to a man one hundred years old? And 6will Sarah, who is ninety years old, bear a child?”

18And Abraham said to God, “Oh that Ishmael might live before You!”

19But God said, “No, but Sarah your wife will bear you 7a son, and you shall call his name 8Isaac; and 9I will establish My covenant with him for an everlasting covenant for his 10descendants after him.