Paul continues his argument how the gospel is about making the righteousness of God to be revealed by comparing God to men. In the previous verses, he used David as a example of how God used David's unrighteousness to cause His righteousness to be seen. The example was not because David was a special case. All men are born under sin and there is no way for them to escape it. There are none righteous. There are none who seek God, so Paul quotes from Psalm 14. Psalm 14 explains the picture of the creation of Eve. God looked through the whole world and could find none comparable to Him, so He had to create His bride. That is the same argument that Paul is making in this passage. No one desires the righteousness of God, so God has to do the work to create those who do.