(Proverbs 24:18 KJV) Lest the LORD see it, and it displease him, and he turn away his wrath from him.
Do you need a reason to love your enemies and bless those who persecute you? Here you have it. It might be a little twisted but the point is the same. To put is simply, if you say “Yes!” when someone who is your enemy has a tragedy, if you feel that they have finally received what they deserve, if it pleases you, then God will “turn away” (7725) His “wrath” (anger NASB) (639).
God wants us to have the mind of Christ. He wants us to live a life based on love, not revenge. I don’t think we need to worry about that initial, unplanned response. I think we do need to worry about the gloating.
So? It is a bit counter-intuitive, but you only help your enemies by enjoying their pain.