Paul begins his letter by telling us that He is a bondservant of the gospel of God, promised long ago through His prophets in the Holy Scriptures, concerning the coming of the Messiah, the Son of God “born of the seed of David according to the flesh, and declared to be the Son of God with power according to the Spirit of holiness, by the resurrection from the dead”. Under the Old Covenant, God’s holy laws were external. But after God made His Holy Spirit available to the Church under the New Covenant, now His laws can be written in our hearts and minds (Jer 31:33).
After declaring who Jesus is—both man and Son of God, resurrected from the dead and deserving of the title “Our Lord”—Paul returns to identifying himself to his readers. It turns out that Paul’s identity cannot be separated from that of Jesus. “Through Him we have received grace and apostleship for obedience to the faith among all nations for His name” (Rom 1:5). It is through belief in Jesus that we has received grace, which is unearned favor, as well as apostleship, which gives us all the authority to speak about salvation in Christ. Paul has been sent by Christ, for the sake of Christ’s name—or for the sake of His honor—to bring about the “obedience of faith”.
That’s a very specific phrase. Paul has not been sent by Christ to get people to obey the law of Moses. He has been sent to bring about obedience to faith in Christ. In other words, Christ calls people to believe in Him. To refuse to believe in Jesus is to disobey that call. Believing is obedience, both in becoming a Christian and walking in Christ throughout our lives.
In one manner or another, we all receive the call to faith in Christ, where we will find His grace. But we must choose to believe. “For God so loved the world that He gave His only begotten Son, that whoever believes in Him should not perish but have everlasting life. For God did not send His Son into the world to condemn the world, but that the world through Him might be saved. He who believes in Him is not condemned; but he who does not believe is condemned already, because he has not believed in the name of the only begotten Son of God.” (John 3:16-18)
He gives everyone more than one chance to believe, but each time someone says “no” their hearts harden. Each of us who believe must share the gospel with others, and that is our obedience as His followers. “Beware, brethren, lest there be in any of you an evil heart of unbelief in departing from the living God; but exhort one another daily, while it is called ‘Today’, lest any of you be hardened through the deceitfulness of sin.” (Heb 3:12-13) Speaking His truth to others is truly loving one another.