here are many passages in the book of Psalms where we will find prayers of imprecation. That is, we will find godly men praying prayers of judgment against evil men. Are these prayers ever appropriate? If so, when; or under what circumstances should we pray for justice instead of mercy? In the sermon notes from an old sermon, I found a list of 5 criteria that might make an imprecatory prayer appropriate: when the innocent are abused, when God is blasphemed, when truth is twisted, when rebellion persists or when the gospel is hindered. Of course, sometimes imprecatory prayers would surely be inappropriate: if hope remains or if we are praying in bitterness or vengeance.
Notice the negative requests in Psalm 5:10, rather severe, no? Yet, at the very least we should note that this one verse was founded upon a number of assumptions about God's perspective concerning wicked men. "God has no pleasure in wickedness." "Evil can't abide in God's presence" (Psalm 5:4). "Foolishness isn't acceptable to God." "God hates evil" (Psalm 5:5). "God destroys lying and murderous men" (Psalm 5:6). So, based upon the guilt of the ungodly and the justice of Jehovah, David prayed for judgment upon his enemies (Psalm 5:8), but not just because they were his enemies. They were passionate enemies of God.