Genesis 17:16

13 He that is born in thy house, and he that is bought with thy money, must needs be circumcised: and my covenant shall be in your flesh for an everlasting covenant.

14 And the uncircumcised male-child, whose flesh of his foreskin is not circumcised, that soul shall be cut off from his people; he hath broken my covenant.

15 And God said to Abraham, As for Sarai thy wife, thou shalt not call her name Sarai, but Sarah [shall] her name [be].

16 And I will bless her, and give thee a son also by her: yea, I will bless her, and she shall be [a mother] of nations; kings of people shall proceed from her.

17 Then Abraham fell upon his face, and laughed, and said in his heart, Shall [a child] be born to him that is a hundred years old? and shall Sarah, who is ninety years old, bear?

18 And Abraham said to God, O that Ishmael might live before thee!

19 And God said, Sarah thy wife shall bear thee a son indeed; and thou shalt call his name Isaac: and I will establish my covenant with him for an everlasting covenant, [and] with his seed after him.