7. Nor are all Abraham's descendants the children of God. God said to Abraham, “It is through Isaac that you will have the descendants I promised you.”
8. This means that the children born in the usual way are not the children of God; instead, the children born as a result of God's promise are regarded as the true descendants.
9. For God's promise was made in these words: “At the right time I will come back, and Sarah will have a son.”
10. And this is not all. For Rebecca's two sons had the same father, our ancestor Isaac.
13. As the scripture says, “I loved Jacob, but I hated Esau.”
14. Shall we say, then, that God is unjust? Not at all.