What does Romans 3:11 mean?

Paul is citing Psalm 14 to back up his statement that all people, both Jews and Gentiles, are "under sin." The previous verse is one of the most-often quoted in the Bible, which states clearly that no person—not even one—is righteous before God on their own merits. That verse began a quote that continues here. Paul's version here shortens what David wrote in Psalm 14:2: "The Lord looks down from heaven on the children of man, to see if there are any who understand, who seek after God."

The point of David's original statement was that God did not declare all of humanity guilty of sin after a quick glance. God was not merely noticing the worst examples of humanity. He symbolically "searched" to see if anyone understood God or looked for Him. Nobody did. This is a crucial truth, one fundamental to the gospel: nobody seeks after God without help from Him to do so. We don't get it, and we don't want to. That's our nature.