Romans 9:7-9

Living Bible

⁷ Just the fact that they come from Abraham doesn’t make them truly Abraham’s children. For the Scriptures say that the promises apply only to Abraham’s son Isaac and Isaac’s descendants, though Abraham had other children too. ⁸ This means that not all of Abraham’s children are children of God, but only those who believe the promise of salvation which he made to Abraham.

⁹ For God had promised, “Next year I will give you and Sarah a son.”