Satan

A description given to describe evil thoughts, bad thoughts common to all people. To describe anger/rage/depression. It's like as if, when you have a bad day, and you're angry, or life just isn't working out and you feel like harming yourself. Or you have thoughts of tricking people, being mischievous for your own gain from their loss. Just thoughts in general most would wish they didn't / shouldn't have. When consumed by the aforementioned thoughts the word Satan was given to describe that sometimes over-whelming feeling. Everyone has those thoughts and feelings at some point or another. When you're just 'filled' with that anger, you could almost describe it like something entered you, you weren't yourself. Satan was the name given to that fictitious entity. At least in the books of 'Job, Matthew, Mark, Luke'. Some of the other books seem to take him as a literal / physical entity. The whole definition of it seems to become skewed throughout the passages referencing it. It's just human beings having evil thoughts, thinking of doing bad things; Not wanting those thoughts, as a form of coping with those thoughts, they gave it a name, and that name is Satan.