15 Then God said to Abraham, “As for Sarai your wife, do not call her Sarai, for her name is to be Sarah.
16 And I will bless her and will surely give you a son by her. I will bless her, and she will be the mother of nations; kings of peoples will descend from her.”
17 Abraham fell facedown. Then he laughed and said to himself, “Can a child be born to a man who is a hundred years old? Can Sarah give birth at the age of ninety?”
18 And Abraham said to God, “O that Ishmael might live under Your blessing!”
19 But God replied, “Your wife Sarah will indeed bear you a son, and you are to name him Isaac. I will establish My covenant with him as an everlasting covenant for his descendants after him.
20 As for Ishmael, I have heard you, and I will surely bless him; I will make him fruitful and multiply him greatly. He will become the father of twelve rulers, and I will make him into a great nation.
21 But I will establish My covenant with Isaac, whom Sarah will bear to you at this time next year.”
22 When He had finished speaking with Abraham, God went up from him.