And, predicting that God would consider the Gentiles right with Him by [their] faith, the Scriptures previously recorded [this promise of] the Gospel to Abraham by saying [Gen. 12:3], "All nations will receive a blessing through your descendant [i.e., Jesus]."

Now [specific] promises were made to Abraham and to his seed [i.e., descendants]. [God] did not say "seeds" [plural] as though He were referring to many persons but "seed" [singular] showing that He meant one [descendant]; [Gen. 13:15 says] "And to your seed," referring to Christ.

For it is written in the law about Abraham's two sons [Gen. 16]; one [was] by his slave woman [Hagar] and the other by the free woman, [his wife, Sarah].

What does the Scripture say about this matter? [It says, Gen. 21:10-12], "Get rid of the slave woman [Hagar], with her son [Ishmael]; for the son of the slave woman [Ishmael] will not inherit [what God promised to Abraham and his descendants], along with the son of the free woman [i.e., Isaac]."

But when I saw that they did not walk uprightly according to the truth of the gospel, I said to Peter, before them all: If you, being a Jew, live after the manner of the Gentiles, and not after the manner of the Jews, why do you compel the Gen tiles to observe Jewish customs?