There is no devil, no satan, no evil spirit that's going to come in the night and suck your soul out of you. There ARE forces that will act upon you only if you allow them to and you are in an egotistical state of being. Ego is the devil and evil is done by humanity.
So when people say the devil made them do it, translation, they allowed their murderous ego to run amok. They were thinking and feeling the control of their ego and were weak in Spirit and, again, allowed this egoic force to propel them.
We are talking about the so-called lower mind and ego where the reptilian part of us has more reign. Remember that the reptilian brain's manta is "eat or be eaten." This is prevalent on our planet and is why I suggest the wisdom path, the path away from this type of thinking.
Please also remember that we live in a dualistic construct which allows for good AND bad. We have given ourselves the bad to more appreciate the good. When that lesson is learned, we don't need to experience bad any more. We can choose to experience the qualities of Spirit: love, compassion, wisdom, peace, kindness, tolerance, grace, ease and abundance. Life does have ups and downs and you have the power to control this.
Spirit is real, not the devil. When you are thinking and feeling spiritually, you are diametrically opposed to lower ego, the devil and all the bad forces.
Stay with and in Spirit. Let your Spirit direct you. It will never, ever harm.