Should we rejoice in the demise of an evil man who has received deserved justice? Romans 13:4 tells us that our governing authorities are "an avenger who carries out God's wrath on the wrongdoer." And then there are passages like Psalm 58:10-11 "The righteous will rejoice when he sees the vengeance; he will bathe his feet in the blood of the wicked. Mankind will say, 'Surely there is a reward for the righteous; surely there is a God who judges on earth.'" Proverbs 11:10 "When it goes well with the righteous, the city rejoices, and when the wicked perish there are shouts of gladness."
Or, should we be mourning another unrepentant sinner now suffering in unspeakable torment? Ezekiel 33:11 (or see 18:23) says, "Say to them, As I live, declares the Lord GOD, I have no pleasure in the death of the wicked, but that the wicked turn from his way and live; turn back, turn back from your evil ways; for why will you die, O house of Israel?" Proverbs 24:17 "Do not rejoice when your enemy falls, and let not your heart be glad when he stumbles."
So which is it? It seems that much of what I have seen or read (with some exceptions) has emphasized one of these perspectives or the other. The Bible clearly teaches the necessity and certainty of justice being done for unrepentant sinners. It shows the gladness of the righteous at the execution of that justice. The carrying out of justice brings glory to God and that is reason for rejoicing. (Were Moses, Miriam, and all of Israel wrong to rejoice at the demise of the oppressive Egyptians - Exodus 15?) But the Bible also teaches us love for the souls of the lost, a desire to see them saved, and not taking pleasure in the death of those who remain in that lost condition. What a sobering thought that we deserve the same punishment, and except for the grace of God shown to us in Christ, we would receive it; another has died without that grace.
Some won't like this, but I believe our response should be both rejoicing and mourning; a feeling of gladness and relief, but also of sorrow. We don't require a choice between God's sovereignty and man's responsibility. We believe in both without apology. So too here. "For everything there is a a season, and a time for every matter under heaven...a time to weep, and a time to laugh; a time to mourn, and a time to dance" (Ecclesiastes 3:1,4). Scripture is balanced. We should be too.