Genesis 17:20

Then Abraham fell on his face, and laughed, and said in his heart, “Will a child be born to him who is one hundred years old? Will Sarah, who is ninety years old, give birth?”

Abraham said to God, “Oh that Ishmael might live before you!”

God said, “No, but Sarah, your wife, will bear you a son. You shall call his name Isaac. I will establish my covenant with him for an everlasting covenant for his offspring after him.

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

When he finished talking with him, God went up from Abraham.

Abraham took Ishmael his son, all who were born in his house, and all who were bought with his money: every male among the men of Abraham’s house, and circumcised the flesh of their foreskin in the same day, as God had said to him.