Romans 9:7-9

World English Bible

⁷ Neither, because they are Abraham’s offspring, are they all children. But, “your offspring will be accounted as from Isaac.”Genesis 21:12 ⁸ That is, it is not the children of the flesh who are children of God, but the children of the promise are counted as heirs. ⁹ For this is a word of promise, “At the appointed time I will come, and Sarah will have a son.”Genesis 18:10,14