Complex sentence: Not only is he killing murderers, he also kills people for minor crimes, such as petty theft, his current lack of a human host depriving him of the ability to effective judge the sins committed in their appropriate context.
Split into simpler sentences: Not only is he killing murderers, he also kills people for minor crimes, such as petty theft. His current lack of a human host depriving him of the ability to effective judge the sins committed in their appropriate context.