Romans 1:18-32 is a summary judgment against the Gentiles. In legal terms, a summary judgment may be issued when it is obvious there is no need to go to trial. Either the evidence is totally lacking and the case without merit, or the evidence proves a case on its face. In Romans 1, the unrighteousness and vile conduct of the Gentiles was evident to all so as not to warrant a defense.
In Romans 2, Paul turns his attention to his Jewish brethren. While the conduct of the Gentiles was evident, the guilt of the Jews was less so, being more cryptic as it was hidden or shaded by the Jewish cloak of the observance of the Law of Moses.
Paul pulls back the cover of the Jews’ observance thereof and shows them to be equally guilty in the eyes of God. Paul exposed their hypocrisy as those who condemn others for sins that they themselves also committed. Moreover, as the Gospel was given to the Jew first and then the Gentile (1:16), so also would the indignation and wrath of God be meted out against the Jew first and then the Gentile (2:8-9).
Using the Law and making their boast therein, they condemned those who steal while they themselves also were thieves. They also condemned adultery and idolatry while practicing the same. They condemned idolatry while practicing sacrilege. Though they made their boast in the Law, they dishonored God through breaking the Law. Their hypocrisy was so evident that, because of them, the name of God was blasphemed among the Gentiles.
One might rightly inquire, “How did the Jews do all these things while under the Law?” The answer lies in the Jewish observances of their traditions, which they mistook for observing the Law.
For example, Jesus condemned their practice of Corban in Mark 7. Corban was a Jewish financial loophole that allowed them “dedicate” their goods “as a gift to God” (via the hands of the Pharisees – TC) to the neglect of providing care of their own parents. Thus, they rejected God’s command to “honor your father and your mother” (Ex 20:12) in the pursuit of their traditions. Jesus concluded this condemnation saying, “And many such things you do” (Mark 7:9-13).
We have an old saying around here: “Make sure your own porch is swept before telling me I need to sweep mine.” Those Jews needed a big broom!