Romans 9:8-10

King James Version

⁸ That is, They which are the children of the flesh, these are not the children of God: but the children of the promise are counted for the seed.

⁹ For this is the word of promise, At this time will I come, and Sarah shall have a son.

¹⁰ And not only this; but when Rebecca also had conceived by one, even by our father Isaac;