19 Then God said, “Yes, but your wife Sarah will bear you a son, and you will call him Isaac.a I will establish my covenant with him as an everlasting covenant for his descendants after him.

Read Genesis 17:19 Using Other Translations

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.
God said, "No, but Sarah your wife shall bear you a son, and you shall call his name Isaac. I will establish my covenant with him as an everlasting covenant for his offspring after him.
But God replied, “No—Sarah, your wife, will give birth to a son for you. You will name him Isaac, and I will confirm my covenant with him and his descendants as an everlasting covenant.