And God said unto Abraham, Let it not be grievous in thy sight because of the lad, and because of thy handmaid; in all that Sarah saith unto thee, hearken unto her voice; for in Isaac shall thy seed be called.
And God said, Nay, but Sarah thy wife shall bear thee a son; and thou shalt call his name Isaac: and I will establish my covenant with him for an everlasting covenant for his seed after him.