What does Psalm 9:19 mean?

David exclaims, "Arise O LORD." When the Hebrews traveled through the Negev, the ark of the covenant went before them. Numbers 10:35 quotes Moses as saying, "Arise, O LORD, and let your enemies be scattered, and let those who hate you flee before you." Like Moses, David recognized that God is all-powerful, but His enemies were weak. "Man," as used here, means weak, frail human beings. David knew the Lord would not allow such enemies to have ultimate victory.

The prayer offered here is for God to judge "the nations." This phrase is most commonly used in the Old Testament in reference to all people groups other than the nation of Israel. In other words, it is mostly a reference to Gentiles—non-Jews—and often serves as a symbolic reference to the ungodly world.

Someday the Lord Jesus Christ will judge the nations. He will judge in the sense of punishing them (Revelation 19:15–16). He will adjudicate by determining who will enter His earthly kingdom and who will perish. The judging will be based on how nations treated the saved Jews during the tribulation (Matthew 25:40). The saved Gentiles believed the saved Jews' gospel of the kingdom (Matthew 24:14), which provided sanctuary for them.