(Psalm 9:7) “But the Lord shall endure forever: he hath prepared this throne for judgment.”
I wonder, if man were not sinful, would God not have to set up his throne for judgment? His throne would be for ruling, but it would not have to be for discovering and pronouncing punishment of the wicked. But since there are the wicked, God is preparing his throne for a time when they will be brought to account for their transgression of God's will. God will outlast any hope of the wicked for covering up, or justifying, or getting past their wicked deeds (hoping the deeds will be forgotten). From the time a wicked act is performed God's judgment throne is ready to pronounce a punishment for that act. The time in court will come.
Let us not forget judgment of wrong doing is not only for the wicked: (v18) “For the needy shall not always be forgotten: the expectation of the poor shall not perish forever.” Since vengeance is from the Lord, the downcast will also have their day in court. There will also be recognition of those who have repented.
