What does Psalm 9:16 mean?

David acknowledges that God's involvement in the world is not impossible to see (Romans 1:18–20). Especially in bringing defeat to Israel's enemies, God has shown He is righteous.

Although this statement explicitly refers to what happened to David's enemies, it relates to future judgment as well. At Jesus' return to earth (Revelation 19:11–16), He will vindicate His people and punish the wicked (Jude 1:14–15). The wicked pursed a life of sin, and their sin will repay them with a bitter payoff (Romans 6:23).

Zechariah 14:1–2 foretells a day when the Lord gathers all nations against Jerusalem to battle. Their armies will capture the city, plunder it, and rape its women, but the Lord will "go out and fight against those nations" (Zechariah 14:3). The fate of those who so violently oppose God is clear: "The LORD will strike all the peoples that wage war against Jerusalem: their flesh will rot while they are still standing on their feet, their eyes will rot in their sockets, and their tongues will rot in their mouths" (Zechariah 14:12).

This verse includes an obscure term, higgaion, which is not clearly understood. Most scholars believe it's use here implies a musical instruction. The Hebrew word itself can imply whispering (Lamentations 3:62), meditation (Psalm 19:14), or something which "resounds," such as music (Psalm 92:3). The use here, as what seems to be a set-apart term, is unique. This might be an indication of a particular kind of musical interlude. Since the introduction to this psalm may reference a tune to which these words are meant to be sung (Psalm 9:1), this seems likely.