When Paul began his letter to the Romans, “For I am not ashamed of the gospel of Christ” (1:16), he didn’t mean the gospel about Christ but the gospel Christ Himself preached as evident by how he ended his letter, “the preaching of Jesus Christ” (16:25). The true gospel message, the message that saves, is the message the Savior Himself preached. Paul’s entire letter of Romans is defining and explaining the gospel Christ preached. Salvation or eternal life isn’t according to our beliefs but according to our actions, “Who will render to every man according to his deeds [actions]: To them who by patient continuance in well doing seek for glory and honour and immortality, eternal life” (2:6-7). “I know thy works [actions]” (Rev 2:2,9,13,19,3:1,8,15), “And, behold, I come quickly; and my reward is with me, to give every man according as his work [actions] shall be” (Rev 22:12).
Jesus Christ preached, “Think not that I am come to destroy the law, or the prophets: I am not come to destroy, but to fulfil” (Mat 5:17), “Therefore all things whatsoever ye would that men should do to you, do ye even so to them: for this is the law and the prophets” (Mat 7:12). That “this is” the law and the prophets is that this one commandment of doing good is the satisfying of all that was required in the law and the prophets. With regards to the requirements of the Old Covenant law, there’s a distinction between the moral and the formal, the righteous and the ritualistic. There’s no change in what’s morally and righteously required of God’s people from the Old Covenant to the New—Christ preached the same righteous standard. What changed is the formal and ritualistic from which Christ set us free, “Stand fast therefore in the liberty wherewith Christ hath made us free” (Gal 5:1).
In Christ’s Sermon on the Mount, He said nothing of believing but everything of obeying. He began the main portion by declaring, “That except your righteousness shall exceed the righteousness of the scribes and Pharisees, ye shall in no case enter into the kingdom of heaven” (Mat 5:20). If we don’t live righteously according to the standard He taught in this Sermon, then in no case, without exceptions, will we enter His Kingdom. Toward the end of His Sermon, “And then will I profess unto them, I never knew you: depart from me, ye that work iniquity [anomia 458]” (Mat 7:23), “you lawbreakers!” (NET), “you who practice lawlessness!” (NKJV). The Greek anomia is contempt, transgression, or violation of law. And He ended His Sermon with, “Therefore whosoever heareth these sayings of mine, and doeth them … And every one that heareth these sayings of mine, and doeth them not” (Mat 7:24,26). It’s simple—if we do what He commanded we’ll be saved, but if we don’t we won’t be, “And why call ye me, Lord, Lord, and do not the things which I say? Whosoever cometh to me, and heareth my sayings, and doeth them … But he that heareth, and doeth not” (Luk 6:46,47,49).
Jesus Christ preached that we must fulfil the righteousness of the law: “I am not come to destroy, but to fulfil” (Mat 5:17); “That except your righteousness” (5:20); “But seek ye first the kingdom of God, and his righteousness” (6:33); “this is the law and the prophets” (7:12). And this was Paul’s gospel: “Therefore if the uncircumcision keep the righteousness of the law … if it fulfil the law” (Rom 2:26-27); “That the righteousness of the law might be fulfilled in us” (8:4); “for he that loveth another hath fulfilled the law … love is the fulfilling of the law” (13:8,10).
Jesus Christ preached faithfulness to Him as Lord: “Who then is a faithful and wise servant” (Mat 24:45); “Well done, thou good and faithful servant: thou hast been faithful over a few things” (Mat 25:21); “Well, thou good servant: because thou hast been faithful in a very little” (Luk 19:17); “He that is faithful in that which is least is faithful also in much” (Luk 16:10). And He preached that unfaithful servants will perish, “The lord of that servant … shall cut him asunder, and appoint him his portion with the hypocrites” (Mat 24:50,51), “And cast ye the unprofitable servant into outer darkness” (Mat 25:30). But to convey a different gospel message, throughout the New Testament the Greek noun [pistis 4102] and verb [pisteuo 4100] have been translated as “faith” and “believe” respectively, rather than “faithfulness” and “trust.” But Abraham isn’t our example of faith but of faithfulness: “because thou hast obeyed my voice” (Gen 22:18); “Because that Abraham obeyed my voice, and kept my charge, my commandments, my statutes, and my laws” (Gen 26:5); “So then they which be of faith [faithfulness] are blessed with faithful Abraham” (Gal 3:9). Furthermore, not even once were the early Christians called “believers,” but translations have been fudged to read that way: “All the believers were together” (Act 2:44 NIV); “All the believers were one in heart and mind” (4:32); “And all the believers used to meet together” (5:12).
The gospel of Christ is obedience to Him: “But they have not all obeyed the gospel” (Rom 10:16); “that obey not the gospel of our Lord Jesus Christ” (2Th 1:8); “he became the author of eternal salvation unto all them that obey him” (Heb 5:9).