What does Paul's teaching about Gentiles and the promises to the fathers reveal about God?
Paul's teaching shows God's promises to Abraham, Isaac, and Jacob were not limited to Israel. When Israel rejected the Messiah, the message went to the Gentiles, so that they too might glorify God for His mercy. This reveals God as merciful and gracious, extending His covenant promises to Gentiles.
Les explains that God had promised Abraham a nation, a land, and that He Himself in the person of the Son would come as their Messiah, King, and Redeemer. Those promises and covenants were made to the fathers—Abraham, Isaac, and Jacob—and He came to Israel first to confirm them. But after Israel's crescendo of rejection, culminating in the stoning of Stephen, Paul goes to the Gentiles. Through the promises made to the fathers, the Gentiles might glorify God for His mercy. Les emphasizes that this is the mercy and grace of God.