Do you have "evil" thoughts?
Have you had one in the past?
Do you consider betrayal of trust "evil?"
Do you face temptation from that which you think you should resist?
Do you believe "evil" is a reality?
If your answer is "no" to any or all of the above for some generic reason like thoughts are just part of the experience of the human animal, then what stops you from acting on them since they can't be "wrong"? Being just chemical reactions in the brain and all?