Then God said to Abraham, "As for Sarai your wife, you shall not call her name Sarai, but Sarah shall be her name.
Genesis 17:15
Surrounding context
17:14 And the uncircumcised male child, who is not circumcised in the flesh of his foreskin, that person shall be cut off from his people; he has broken My covenant."
17:15 Then God said to Abraham, "As for Sarai your wife, you shall not call her name Sarai, but Sarah shall be her name.
17:16 And I will bless her and also give you a son by her; then I will bless her, and she shall be a mother of nations; kings of peoples shall be from her."