Some religions, particularly Christianity, have a concept in which demons or evil spirits can enter a person's body and take control of them.
Does Judaism have a concept similar or like this? The literal translation of I Samuel 16:23 would imply such a thing can happen, but I have always been taught the Rabbinical tradition that it was not an actual evil spirit disturbing Shaul HaMelech, but a mental illness. (Source?)
This is not a question of comparative religion; I have mentioned Christianity only to serve as an example so others maybe will understand what I am talking about.