I don't believe that an evil one such as a devil with horns and a pitchfork exists; however, there is detrimental energy all around us. Empaths feel this as well as picking up on positive energy.
How can we be more selective and pick up only what will benefit us? Let's say detrimental energy is the evil one. It might include the pulling or draining we feel around certain folks who inadvertently siphon our energy when we are not keenly aware of our own energy. I'm not saying that any person is evil—all they want is love and light. What they may not realize is that love and light is readily available from within themselves. It is in each of us because we are sparks of the Divine, which is love and light.
So how can we help these energy vampires without allowing them to drain us? By being filled with love and light—pure Source Consciousness—we broadcast light so strong that when a detrimental dart comes toward us, our energy deflects it like a feather being blown into a fan.
This short audio explains more.
PURCHASE paperback book, Whose Stuff Is This? Finding Freedom from the Thoughts, Feelings, and Energy of Those Around You at http://tinyurl.com/EmpathAmazon. The e-book version is now available for Kindle, iPhone, iPad, and other digital reading devices.