“But if our unrighteousness demonstrates the righteousness of God, what shall we say? The God who inflicts wrath is not unrighteous is He? (I am speaking form a human viewpoint). Far from it! For otherwise, how will God judge the world” (Romans 3:5-6).
The righteousness of God, his predilection to make right the corruption of his created order, demands his wrath be meted out at the judgment in a way that is impartial (2:11). This in contrast to a world that distributes a form of justice favoring wealth, the well-connected, or those of a particular ethnicity. To be truly righteous, the nature of God does not allow him to wave off the sins of Israel, because of some perceived favored nation status clause within the covenant, while punishing the sins of the Gentiles. God’s righteousness will demonstrate upon a cross his covenant faithfulness, and a judgment upon sin that is fair, evenhanded, and once and for all.