What does Psalm 59:8 mean?

Although David's enemies (Psalm 59:1–2) thought there would be no consequences for their evil actions (Psalm 59:7), they were deeply wrong. David celebrates that God knows everything men do (Hebrews 4:13) and will hold each one accountable (Matthew 12:36–37). God is depicted as "laughing" here, in the sense of irony (Psalm 2:4). The idea that anyone—even an entire nation—could defy Him is ridiculous. "The nations" is a phrase often used in reference to Gentiles, and more broadly as those who set themselves up as enemies of the God of Israel.

This statement is meant to contrast the "howling" and "bellowing" of wicked men with the righteousness of God. All who oppose the Lord and His people may snarl and snap, but God takes notice, and He will judge them. The reaction depicted here echoes the scene that unfolds in Psalm 2. The unbelieving nations rage against the Lord and the Messiah. They plot to overthrow God's rule, but "He who sits in the heavens laughs; the Lord holds them in derision. Then he will…terrify them in his fury…shall break them with a rod of iron and dash them in pieces like a potter's vessel" (Psalm 2:4–9). Romans 6:23 declares that "the wages of sin is death." Those wages have never been reduced, and pay day is coming for all who oppose God, righteousness, and His people.