We can then reasonably conclude that “evil” exists because “will” exists. And it goes without saying that God wants you to exercise your will to His greater glory - even though you are not FORCED to. Ergo, the problem
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And while we may insist that God and “evil” cannot abide together (which is true), God obviously understands “evil” because he judges and punishes it - which explains how He can create a being (Lucifer) to enact it apart from Himself.
You could reduce your question (in another post) even further to “Why did He make all this junk (the universe) anyway?” And as we can’t get inside the mind of God, but know that’s He’s all powerful, we can reasonably deduce that the answer is this - He wanted to.
As your “label” indicates you’re looking for truth, I’ll share with you why I’m working to be a member of the Pope’s team.
I am a theist because theism is the only rational basis for morality.
I am a Christian theist because I think Christianity best represents the complex interface between the Divine and Human Conditions in a redemptive context.
I am a Catholic because Christian Truth derived from “Personal Divine Revelation” (Protestantism) is chaos. Plus, I can make a way better historical and theological argument for it than I can any other Christian sect (although I respect the Eastern Orthodox and Oriental Orthodox Communions enormously - we were brothers once).
I hope I have been helpful.
Go in Peace.