I had a query from a reader about demonic possession. They had a specific question about their experience, but I suspect that the general question of possession is something people have interest in. Therefore, I'll opine a little on this subject.
Possession is a no-brainer in the New Testament. Jesus casts out demons many times. The church catholic (small c - universal church) has recognized possession since very early on, and one of the minor orders was that of exorcist. Although the minor orders no longer exist (as of Vatican II), some priests are still trained as exorcists.
The problem is, many of the things that were thought of as “possession” in the old days are now commonly curable physical or mental diseases. At one time, most sickness was thought of as being caused by demons. We no longer believe that - as we can see evidence of cures that have nothing to do with religious means.
However, I have had enough experience to believe that there IS something beyond what science can explain. I believe that there are spiritual forces that have the ability to interact with humans, sometimes negatively. I don’t have a lot of specific experience and I am not trained as an exorcist (not many Episcopal priests are.) The line between mental illness and possession is a very hard one to discern.
My class once asked Bp. Mark Dyer, who teaches at Virginia Theological Seminary (and was trained as an exorcist back when he was a Roman Catholic priest) how someone could become possessed if they had been baptized. This is especially troubling because in baptism we mark a person as Christ's own forever. He answered that it was possible for a person who has become apostate (falling away from the church) to become "empty" while maintaining the mark of baptism. In this case, it is like the old adage, "Nature abhors a vacuum." If a person will not allow God to fill that void, then something else will.
In any case, I think it is important to treat people who claim to be possessed seriously. Even if their symptoms are created by a psychosis rather than a possession, the rite of exorcism might be efficacious as a placebo. In any case, prayer is never wasted. However, I think Psychologists/Psychiatrists should be included in the diagnosis and treatment. One would think that if you WERE possessed, some serious psychological problems might persist even after exorcism.
BTW, the graphic is from the Steve Jackson Role-Playing Game In Nomine.