Ro 12:19 Beloved, do not avenge yourselves, but rather give place to wrath; for it is written, “Vengeance is Mine, I will repay,” says the Lord.
And how do you know the Lord didn't avenge this one? There was no one present except the guy who toasted himself?
Also, the Lord works His vengeance through men. Did you not know that? Governmental authority exercises God's wrath.
Romans 13:3,4: "For rulers are not a terror to good works, but to the evil. Wilt thou then not be afraid of the power? do that which is good, and thou shalt have praise of the same: For he is the minister of God to thee for good. But if thou do that which is evil, be afraid; for he beareth not the sword in vain: for he is the minister of God, a revenger to execute wrath upon him that doeth evil."
The sword in verse 4 is an instrument of death. It is entirely appropriate for Christians to wish justice upon lawbreakers. That's all I have seen on this thread.