But God said to Abraham, “Don’t be troubled about the boy and the slave woman. Do whatever Sarah tells you. The descendants I promised you will be from Isaac.
God said, “No, Sarah your wife will have a son, and you will name him Isaac. I will make my agreement with him to be an agreement that continues forever with all his descendants.
From the beginning I told you what would happen in the end. A long time ago I told you things that have not yet happened. When I plan something, it happens. What I want to do, I will do.
But what does the Scripture say? “Throw out the slave woman and her son. The son of the slave woman should not inherit anything. The son of the free woman should receive it all.”