What is Possession?

It is the phenomenon in which a malign spirit resides in a body and, in certain moments, can use it to speak or move without the person affected being able to resist. The malign spirit does not inhabit the soul, since the soul is, in all cases, free and totally incapable of being possessed. Only the body can be subject to possession.
What are the essential characteristics needed for a diagnosis of possession?
The diagnostic criteria which would have to be present in the subject for us to suspect a possession would be the following:

1.-An arc of sensations, in the presence of sacred or religious realities, which oscillate, according to each person, between annoyance and horror, between slight manifestations of irritation to violent manifestations of rage and infuriation.

2.-In the most extreme cases, the horror would lead to an outburst of fury, normally accompanied by blasphemies or insults directed towards whatever religious object that has been placed in the proximity.

3.-In the most acute episodes of the show of furious rage, the possessed person loses consciousness. When he eventually comes to, he doesn't remember anything. The amnesia is absolute and total. Nevertheless, even though the subject doesn't remember a thing, he did suffer a change of personality which lasted the duration of that crisis of fury. During that crisis, a second personality emerges.

4.-That second personality is always malignant in character. Frequently, during this type of moment, the eyes roll backwards or downwards, leaving the eyes blank. The facial muscles go tense and the hands show contortion. During these moments of crisis, the person uses a voice which is full of hate and anger.

5.-Once the furious crisis finishes, the person gradually returns to normality; the transition back to normality being practically similar in time and mode to the transition which is observed when one returns from a state of hypnosis to a normal state of consciousness.

6.-Outside of these furious crises in which a second personality emerges, the person lives a completely normal life, without the pathology affecting whatsoever his work or social relations. The person appears as a completely sane, capable anytime of distinguishing perfectly between reality and the intrapsychical world. The person does not show any delirious conduct.

7.- In some cases they manifest things which do appear as sensorial hallucinations (concretely, they explain that, sporadically, they see shadows, or feel a faint, strange sensations in some part of their body or the hear creaking noises). On the other hand, they do not hear internal voices nor feel anything moving under their skin.