Diabolic possession

Demonic possession is the process by which individuals are believed to be possessed by malevolent preternatural beings, commonly referred to as demons or devils. Obsessions and possessions of the devil are placed in the rank of apparitions of the evil spirit among humans. It is obsession when the demon acts externally against the person whom it besets, and possession when he acts internally, agitates them, excites their ill humor, makes them utter blasphemy, speak tongues they have never learned, discovers to them unknown secrets, and inspires them with the knowledge of the obscurest things in philosophy or theology.

Descriptions of demonic possessions often include erased memories or personalities, convulsions (i.e. epileptic seizures or “fits”) and fainting as if one were dying. Other descriptions include access to hidden knowledge and foreign languages (xenoglossy), drastic changes in vocal intonation and facial structure, the sudden appearance of injuries (scratches, bite marks) or lesions, and superhuman strength. Unlike in channeling, the subject has no control over the possessing entity and so it will persist until forced to leave the victim, usually through a form of exorcism.

Many cultures and religions contain some concept of demonic possession, but the details vary considerably. The oldest references to demonic possession are from the Sumerians, who believed that all diseases of the body and mind were caused by "sickness demons" called gidim or gid-dim. The priests who practised exorcisms in these nations were called ashipu (sorcerer) as opposed to an asu (physician) who applied bandages and salves. Many cuneiform clay tablets contain prayers to certain gods asking for protection from demons, while others ask the gods to expel the demons that have invaded their bodies.

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