Problem-Of-Evil
Question: How can a good, just and loving God allow evil?
Short answer: Free will allows us to commit evil.
Long answer: Free will entails that God will not intervene with evil doings of man. Some say that evil can be categorizes as moral evil and natural evil, but I don't believe in natural evil.
How can it be evil that I feel pain when I pinch myself? I would argue that natural evil is not really evil because evil is always an immaterial issue. Why makes moral evil, evil? The violation of God. If you murder someone, you are violating the law of God. So how does natural evil violate God? Does nature not operate exactly how God designed it? Nature has no free will of it's own.
For God did not design us to sin, but he provided us with the ability to choose. For God is love, and love is free, and so God gave us freedom. Evil has already taken place before the murderer's knife touches his victim's throat. (POT vs ROT)