Christ became a servant to the circumcised in order to confirm the promises given to the patriarchs, and in order that the Gentiles might glorify God for his mercy. Jesus’ birth accomplishes two very significant things: 1) His Word is upheld as true, and 2) His mercy is displayed for all the world to glorify. God’s faithfulness to the Jews in His covenant promises is realized and His uncovenanted mercy is poured out on people from every tribe and tongue.
In this passage Paul quotes four times from Scripture, once from the Law, once from the Prophets, and twice from the Writings. Each time, the theme is the Gentiles glorifying God. God gave us mercy that we might give Him glory. God did this through Christ’s obedience, that the law might be fulfilled. Christ undid the curse and satisfied God’s wrath. He fulfilled the law that we transgressed in order to make us fit to receive the promises of the covenant.
In the broader context of Romans 14 and 15, Paul is concerned that we learn to endure with our weaker brothers. He calls on God’s people to live in peace and humility. Our joy and peace at Christmastime is founded on the marvelous truth that we have been graciously included in the faithful covenant of God. Our only response is to glorify, exult and imitate this Christ who became a servant.