The Unchanging Promise
Christianity is utterly unique among religions in insisting that it isn’t what we do for God that makes us right with Him, but only what He does for us. This is the radical and offensive idea of grace. It leaves no room for pride, but instead billboards the crucified and cursed Christ in front of our eyes. In this chapter Paul has been arguing that Christians must continue with God the way they began: by faith alone. To be a child of Abraham is to have faith like he did. Anyone who tries to belong to God through the works of law is under its curse, the same curse Jesus bore on the cross for those who look to him. Now Paul explains the nature of God’s promise to Abraham, His unchangeable covenant of grace.