A common practice in the Bible was the casting out of demons, or the exorcism. This practice has a long history, just as science does. With the advances in science, exorcists are aware that there is many other explanations for what may seem like a possession.
One of the disorders that was probably common mistaken for a possession is Tourette Syndrome. This is a Tic disorder, which are characterized by involuntary movements and vocalizations.
Another might be epilepsy, where one can have convulsions during what may seem to be an exorcism, and may pass as if one were exorcised.
Other disorders may include various types of neurological disorders and mental health issues.
This is not to say that demon possession does not exist. Moreover, they are simply rare.
The Catholic Church is now more strict on determining a possession, looking at it as a rare occurrence.
Signs of demonic invasion vary depending on the type of demon and its purpose, including:
- Loss or lack of appetite
- Cutting, scratching, and biting of skin
- A cold feeling in the room
- Unnatural bodily postures and change in the person’s face and body
- The possessed losing control of their normal personality and entering into a frenzy or rage, and/or attacking others
- Change in the person’s voice
- Supernatural physical strength not subject to the person’s build or age
- Speaking or understanding another language which they had never learned before
- Knowledge of things that are distant or hidden
- Prediction of future events (sometimes through dreams)
- Levitation and moving of objects / things
- Expelling of objects / things
- Intense hatred and violent reaction toward all religious objects or items
- Antipathy towards entering a church, speaking Jesus’ name or hearing scripture.