But God said, “On the contrary, Sarah your wife will bear you a son and you must name him Isaac. So I will confirm My covenant with him as an everlasting covenant for his seed after him.
Then the angel of Adonai said to her, Behold, you are pregnant and about to bear a son, and you shall name him Ishmael— for Adonai has heard your affliction.
And I will bless her, and moreover, I will give you a son from her. I will bless her and she will give rise to nations. Kings of the peoples will come from her.”
Yes, I will establish My covenant between Me and you and your seed after you throughout their generations for an everlasting covenant, in order to be your God and your seed’s God after you.
Live as an outsider in this land and I will be with you and bless you—for to you and to your seed I give all these lands—and I will confirm my pledge that I swore to Abraham your father.
When the rainbow is in the cloud, I will look at it, to remember the perpetual covenant between God and every living creature of all flesh that is on the land.”
By faith even Sarah herself received ability to conceive when she was barren and past the age, since she considered the One who had made the promise to be faithful.