There is no shame in the gospel. Paul states that he is not ashamed of the gospel. It seems as if he is familiar with the statement of Jesus from Mark 8.38//Luke 9.26: If any of you are ashamed of me and my words…the Son of Man will be ashamed of you when he comes…
Why would anyone be ashamed of the gospel? We see in 1 Cor. 1.18-31 that the message of the cross is foolishness to those who do not accept it. There may be a temptation to make it more palatable to those who may find it to be foolish. Paul stands firm in his message and is not ashamed of it and will not alter it to suit anyone’s worldview.
The gospel is the power of God. We have seen that the evidence of the Kingdom was Christ’s power (Matt. 11.2-6). It was initially displayed in his ability to display God’s power. It’s ultimate power was the resurrection from the dead and ultimately the power of God is the continuing work of the Holy Spirit in the life of the believer (see Rom. 8.11).
The gospel is salvation. Believing in the gospel saves us from the wrath of God (Rom. 5.9). Salvation in the Old Testament has the connotation of deliverance also from one’s enemies and results in restoration to wholeness.
It begins with the Jews and spreads to the Gentiles. This stems back to the original covenant with Abram. God chose him and his family to be his people and ultimately to bless every other people group in the world.
The gospel reveals God’s righteousness. Righteousness should be understood in terms of a relationship. It is related as well to the salvation that Paul has already mentioned. God is righteous when he fulfills the obligations he took upon himself to be
The gospel must be experienced by faith. God’s righteousness is accessed by human beings from beginning to end by faith. Our acceptance of the truth and the power of the gospel makes God’s righteousness available to us. Our faith in the gospel is what incorporates us into God’s people. And this has been the plan from the beginning. It has been revealed (once again) in God’s previous revelation (the Old Testament). Paul has previously shown (in Gal. 3.7-9) and will reiterate in Romans (chapter 4, citing Gen. 15.6) that our connection to God’s righteousness (that is, our status of an unbroken relationship with him) is accessed by our faith and not our adherence to the Law or our status as members of the chosen people. Paul here finally appeals to Habakkuk 2.4 – “The righteous will live by faith.”
Thus, there is no shame in the gospel. The gospel is the power of God. The gospel is salvation. The gospel reveals God’s righteousness and the gospel must be experienced by faith.
(Help in this section was provided by the commentaries of C. K. Barrett and James D. G. Dunn).