“Le premier contact fut écrasant.” – “The first encounter was overwhelming.” M.-J. Lagrange, Saint Paul: Épître Aux Romains. Études Bibliques. Paris, 1950.
Romans 1:16–17 (ESV) For I am not ashamed of the gospel, for it is the power of God for salvation to everyone who believes, to the Jew first and also to the Greek. 17 For in it the righteousness of God is revealed from faith for faith, as it is written, “The righteous shall live by faith.”
In Romans 1:16-17 Paul states his theme: the Gospel is the power of God for salvation for anyone who believes. Paul begins the letter by stating clearly the real good news is not about the emperor or the empire. The real power for salvation comes from God, not the emperor or the empire.
First, humans are estranged from God, unwilling and unable to respond to the revelation of God in creation (1:18-3:20). Paul demonstrates Gentiles suppress knowledge of God even though he clearly reveals himself in creation, then argues the Jewish people are just as estranged from God because of their own rebellion. By Romans 3:20, there is no one who seeks God nor is there anyone who even tries!
Second, despite human rebellion, God has provided salvation through Jesus Christ (3:21-5:21). Paul uses a courtroom metaphor: the believer is “declared righteous” because of what Jesus has done on the cross. The believer obtains that righteousness through faith, not obedience to the Law or performance of rituals.
Third, those who believe are wholly identified with the death and resurrection of Jesus, therefore they should live a new life in Jesus (Romans 6-8). Those who believe are “dead to sin.” Once slaves to sin, now slaves to righteousness, but Paul goes on to say those who are in Christ are now children of God. The ethical implication of this new relationship with God is that the “in Christ” person is to act like they are part of the family of God. This new status cannot be lost, those whom God justified he will ultimately glorify.
Fourth, someone might object to this promise of faithfulness. God made promises to Israel in the past, and they appear to now be rejected as God’s people. Can we trust God when he says we cannot lose our salvation, since the Jewish people appear to have be rejected as God’s people, despite his promises in the Old Testament. In Romans 9-11 Paul shows that God is faithful to his promises, even those he made to the Jewish people. Paul constructs a detailed theological argument which shows God was not unfaithful in the past and he will act again on behalf of the Jewish people, so that “all Israel will be saved” (11:25-32).
Fifth, the “in Christ” life transforms thinking in every aspect of life. Paul describes this new life as a living sacrifice and transformed thinking (12:1-2). The gospel confronts both Judaism and the pagan world. By living out the life described in Romans 12-15 a Jewish person goes beyond the Law by exercising the law of love in every aspect of their life (very much like Jesus in the Sermon on the Mount). But Paul goes beyond Jesus to discuss how Jews and Gentiles relate to one another (the stronger and weaker in chapter 14). But the life described in Romans 12-15 subverts Roman cultural scripts as well. The one who is in Christ does not pursue his own honor (like a good Roman), but seeks to serve others.