Recap of Romans 2:1-11
Paul challenges the church because he anticipates that they think they are exempt from God's judgement. He questions them if they have really repented and points out that if they are still self-seeking and do not obey the truth, but obey unrighteousness, there will be wrath and fury. He makes a point that God shows no partiality.
"The Jews were ready to appeal to the Law of Moses, which they had and the Gentiles did not. The implication was that in this connection God does show "partiality" (v.11)...Paul shows that what pleases God is not knowledge of the law but obedience to God's will revealed in it. Therefore, God shows no partiality."
Paul addresses the Jews who think they are special because they have the law and know it well. Not only that, but they think they are guides to the blind, light to those who are in darkness, etc. Paul asks them if they practice what they preach (v21). Paul then makes a bold statement: "For, as it is written, "The name of God is blasphemed among the Gentiles because of you" (v24).
"Condemnation results from failure to obey revelation of whatever kind. Jews have transgressed the Mosaic law in particular, emptying circumcision of its real significance. Paul recognizes the privilege of Jewishness... and of circumcision in particular.... But physical circumcision is a symbol of sanctification and renewal of life...(v.25; Deut. 30:6). The reality, not the sign, is the vital thing and may be possessed irrespective of Jewishness (vv. 26, 27)"
Paul anticipates that a distinction will be drawn between Jews and Gentiles because the Jews have God's law. So Paul points out that what matters is a new life and a new heart that truly loves God.
In Chapter 1, Paul greets the church in Rome and explains how he cares about them. Then, he goes on to explain the gospel. He starts by speaking about God's righteous wrath against all ungodliness and unrighteousness of men. Men suppresses the truth in their unrighteousness and exchange the truth about God for a lie and worship and served the creature rather than the Creator.
In Chapter 2, Paul anticipates that his audience will agree with him about God's righteous judgement, but not think that God's judgement applies to them. These are Christian Jews and Christians gentiles. They know God will judge evildoers, but they don't think God will judge them. They think they are invincible. So Paul shifts from speaking generally about mankind, to speaking specifically about his audience.