In his Perelandra trilogy Tolkien's friend C.S. Lewis similarly posited an evil force that dominated the planet, had perverted humanity, and if left unchallenged would ultimately destroy human kind. Theodicy is a question that has never been resolved as far as I can tell. Not only can we not agree on why evil exists, but we can't really agree on what to do about it.The Bible has contradictory advice. God told us that accounts would be and should be settled.
And I will execute great vengeance upon them with furious rebukes; and they shall know that I am the LORD, when I shall lay my vengeance upon them.
And if any mischief follow, then thou shalt give life for life, Eye for eye, tooth for tooth, hand for hand, foot for foot, Burning for burning, wound for wound, stripe for stripe.Jesus told us to resist not evil, turn the other cheek and don't attempt to get our stolen goods back.
But I say to you who hear, Love your enemies, do good to those who hate you, bless those who curse you, pray for those who abuse you. To one who strikes you on the cheek, offer the other also, and from one who takes away your cloak do not withhold your tunic either. Give to everyone who begs from you, and from one who takes away your goods do not demand them back. And as you wish that others would do to you, do so to them.
But Jesus never lived in Detroit...