Then God said, “No, but your wife Sarah will bear you a son, and you will call his name Isaac. I will establish My covenant with him as an everlasting covenant and with his descendants after him.
Then the angel of the Lord said to her, “Behold, you are pregnant and will bear a son. You shall call his name Ishmael, because the Lord has heard your affliction.
I will establish My covenant between Me and you and your descendants after you throughout their generations for an everlasting covenant, to be God to you and your descendants after you.
Sojourn in this land, and I will be with you and will bless you; for I will give to you and all your descendants all these lands, and I will fulfill the oath which I swore to Abraham your father.
The rainbow will appear in the cloud, and I will see it and remember the everlasting covenant between God and every living creature of all flesh that is on the earth.”
By faith Sarah herself also received the ability to conceive seed, and she bore a child when she was past the age, because she judged Him faithful who had promised.