Some people are so offended by the thought that Paul could feel ashamed of the gospel that they pronounce his statement a sort of understatement for effect. But Jesus himself warned his disciples against being ashamed of him, which shows that he anticipated they might be (Mark 8:38). Paul gave Timothy a similar admonition (2 Timothy 1:8, 12). Paul knew that the message of the cross undermines self-righteousness and challenges self-indulgence. Whenever the gospel is faithfully preached, it arouses opposition, often contempt and sometimes ridicule.
How then did Paul (and how shall we) overcome the temptation to be ashamed of the gospel? By remembering that the same message which some people despise for its weakness is in fact “the power of God that brings salvation to everyone who believes.” We know this because we have experienced its saving power in our own lives. God has reconciled us to himself through Christ, forgiven our sins, made us his children, put his Spirit within us, begun to transform us and introduced us into his new community. How can we possibly be ashamed of the gospel?
Moreover, the gospel brings salvation to “everyone who believes: first to the Jew, then to the Gentile.” Saving faith is the great leveler. Everyone who is saved is saved in exactly the same way, by faith. That goes for Jews and Gentiles equally. There is no distinction between them.
Paul’s eagerness to evangelize in Rome arose from his recognition that the gospel is an unpaid debt to the world and the saving power of God. The first gave him a sense of obligation (he had been entrusted with the good news), and the second gave him a sense of conviction (if it had saved him, it could save others). Still today the gospel is both a debt to discharge and a power to experience.
From Reading Romans with John Stott by John Stott with Dale and Sandy Larsen.