Paul loved his Hebrew heritage. Seeing many of his people (though certainly not all of them) reject Jesus as Messiah hurt him. He wrestled with the question, “Had God rejected God’s people?” He found a key in the Genesis 21 story of Abraham’s two sons, Isaac and Ishmael.
Both were genetically Abraham’s children, but only Isaac was the son of promise. Their story showed, Paul said, that “descent” from Abraham was spiritual, not just genetic.

• Scholar William Barclay said Paul concluded “there is more to Jewishness than descent from Abraham, that the chosen people were not simply the entire sum of all of Abraham’s physical descendants.” Paul also told his Galatian converts that “if you belong to Christ, then indeed you are Abraham’s descendants, heirs according to the promise” (Galatians 3:29). How much do you understand about the Hebrew, Old Testament roots of your faith? How might you learn to know and value that more highly?
• Have you ever had—perhaps have now—someone you care about deeply who just doesn’t see the same importance of faith in Christ that you do? Does that cause you grief or concern, as it did Paul? Is there any part of your family or faith heritage that you care about, and yet have felt the need to move away from? Paul loved God, if anything, even more passionately as a Christian than as a Pharisee. What underlying, deeper parts of your heritage can you honor even if you live them in a different way?