***I wanted to ask what are the classic signs of possession and how they’re distinguishable from mental illness.***
The classic signs. One would be the rolling of the eyes, and that’s usually because of an aversion to the sacred. So if someone was to walk into a church or even the parish center—this has happened a number of times—walk into the parish center and they cannot stand to look at the crucifix. Or if they walk into a church and cannot stay or can only stay with great difficulty because of the presence of the Eucharist or a crucifix or another sacramental, or a statue of the Blessed Mother or something.
A knowledge of hidden things can be a sign. So people who know something they have no reason to know, either about me or a situation or to predict the future.
Another sign would be being able to speak in a language they have no competency in. This would usually occur either in a deliverance prayer or a formal exorcism.
The person possessing inordinate strength—that will often come out in an exorcism in cases where the demons are very violent.
The person can have very extreme facial contortions and a change in the voice. Sometimes their whole body language, including their face, can take on the look of a reptile or a snake, and I’ve had that happen a number of times…
In general, the animation of legs and arms during the prayers, where their using their limbs to either intimidate me or put their hands in the form of fists with every intention of using them to injure me or the people around them.