Evil is caused by the rejection of God. All evil is a result of that.
A little parable...
I gave my daughter $20 last weekend and told her she was "free" to spend it however she wished. Although, I recommended see spend it "wisely." The little rascal spent it on candy. Can you believe it? She rejected my recommendation. So, in essence, she is rejecting me. She's essentially saying that I'm not smart enough to know what's best for her, the little snot. Now, in the short-term, she'll ruin her appetite for dinner. But, in the long-term she's probably on her way to obesity and ruining her teeth.
What should I do? I love her, but I can't allow her to make "wrong" choices. Suffering and evil result from "all" wrong choices. So, what choice do I have? I can't force her to listen to my rules. I have to kick her out of the house. A little suffering, going hungry, a few nights in the cold, and she'll come to her senses and come back to me on her own, and realize, that I know what's best for her, and come to realize that I love her more than anything. What do you think? She's only five and might not survive, but that's her own fault. She rejected me.
A few days later... I kicked her out, for her own "greater" good. But, I can't believe it, she had the audacity to call me "evil." I'm glad I learned this now before she got older, and I'm glad I have other "respectful" children. Especially now, they all listen to what I say, and they obey it. But, I'm not sure it's out of love? They seem to fear me. They only "love" me when I do nice things for them, hmmm? How should I punish them and get them to love me for me, for who I am, the wise and knowledgeable, the caregiver and provider that I am? The one that helped bring them into this world, hmmm? Maybe, kick them out for a while and let them suffer? I wonder what God would do, hmmm?