[A part of "nerd sharing nerd things online for the Orthodoxy roleplay" initative", of sorts]
So. We see the WarEra burning around (sometimes in waves), and it is a good moment to speak about nature of evil in the world.
How comes, you may ask, that in a world where there is One Almighty Merciful God, there is evil in the world? Glad you asked!
Nota bene: this issue stands mostly for the Abrahamic religions; other religions usually don't have one God who is at the same time omnipotent and absolutely good, so they don't have this question by extension.
This is seriously one of the eldest disciplines at least in Christianity, and it's called "theodicy", or, in plain English, "vindication of God".
Basically, question of "how there would be evil in the world if God is good and almighty" is older than Christianity itself; first who asked about it was Epicurus (the very ancient Greek philosopher who defined happiness as absence of pain).
The formal name was set by Leibniz (that guy who invented calculus in parallel with Newton and spent half his life in copyright dispute about it), but... well, the trouble is old, and it was investigated by Christianity almost since it started to gain traction. This contradiction in specification had born few fine patches along the way:
Free Will Argument, by Augustin.
Basically, evil is the byproduct of humanity having free will; it's not that God is evil - He just thinks that free will in humans is important enough to allow them doing evil. It works, if we look at man-made evil. It is messed up if we speak of natural disasters - unless, of course, we patch the patches with "oh, and this specific earthquake is punishment for sins", which is lousy explanation. But it's one of oldest, and it holds proper where it holds. Augustin is one of the Fathers of Church not without a reason.
Evil As Soul-Making, by Irenaeus.
Evil is a gym for soul, to make it better through adversity, because you can't be good person if you don't train yourself against real challenges. Sounds cool, noble even. Is messy whenever we speak of how evil is distributed - somehow, hardest battles are often going not to the best warriors but to some random people with zero chance to win.
Optimal Possible World, by Leibniz.
Welp, there are impossibly big set of parameters, and world in which we live is optimized to be most optimal across all possibilities, so we have least possible amount of evil. Sounds nice, but, well, is uncheckable - what are the benchmarks? Also, refuted of sorts by Voltaire, continental-scale troll.
Hush, you know nothing, Job, by authors of Book of Job
Basically, God is unexplainable to us - just as we are unexplainable to cats. So, well, maybe it's all in our heads, and evil is something bad for us, but needed, in the ways we can't understand. Sounds cool, explains not so much, postulates implicitly that "good" for God is word that doesn't mean "gold" for us. Also trolled by Voltaire, but at least it doesn't pose to be a good explanation - it's basically "shut up and calculate", but in theology instead of quantum physics.
Well, God knows it's a bug, he fixes it on schedule, by Origen.
Oh. Origen was cool enough - hard-core to the mega, he decided to cut his balls off to go to Heaven, and he was deemed a dangerous heretic 300 years after his death. But also he had the most logical explanation: "we have evil as temporary condition; at some point in time, every soul put to eternal damnation - even the Big Horned Guy in charge of this damnation, - will be educated, restored to grace and saved; yeah, it sucks NOW, but when time comes, everything will be good, we're just not there". This patch has specific name, apocatastasis, but - yeah, this one is herecy, unfortunately.
As we can see, no approved patches for the trilemma of "good, omnipotent, allows evil to exist" isn't all-encompassing. 23 centuries in the work, and we're still no closer to resolving it properly; there are traditions that imply relaxed stance on omnipotence (in Judaism) or stick to one of selected patches, but it is genuinely one of the most elegant problems in philosophy history...
...which is OK to have messy and unclear if it's used for personal peace of mind - whatever goes for you to make your life easier after encountering evil, goes. But which is less OK when used as propaganda - "oh, in our theology your suffering doesn't matter because God has his unknowable ways" works poorly.
So, the rule stands: if shit happens with you, you can calm yourself in any way. But if someone tries to sell you the easy solution to complex problems be wary of it.
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