How does an exorcism work? Experts explain as ‘The Exorcist: Believer' premieres

When envisioning an exorcism, most probably see a spinning head, an old priest and a young priest, and lots of projectile vomiting.

That, of course, is how it was portrayed in the 1973 movie “The Exorcist” about the demonic possession of an 11-year-old girl.

“The movie was extremely dramatic,” Father Thomas Rausch, a professor of Catholic theology at Loyola Marymount University, recently told NBC LX. “It was Hollywood to the max.”

So, the dozens of movies about possession that have been made since the 1973 hit - including Friday’s release of “The Exorcist: Believer” – may be highly entertaining, but they might not provide the most accurate depiction of an actual exorcism.

With the latest movie set to hit theaters, NBC LX took a deep dive into how exorcisms work within the Catholic Church, including how common they are and why there is such public fascination in the phenomenon.

What is an exorcism?

“There’s really two different kinds of exorcisms, at least within the Catholic tradition,” Rausch said. “One is a very simple prayer for deliverance when someone is troubled by temptations or some kind of evil spirit. It's simply a prayer that anybody could do to ask the person to be delivered from this problem. The formal exorcism is invoking God's power over an evil spirit commanding them to go out from the person.”

While a spinning head is overdramatizing, Rausch said symptoms of a “possessed” individual can include cries, speaking in strange languages, throwing objects or even contortions of the body.

Those symptoms, however, do not necessarily indicate the internal presence of a demon.

“It’s interesting that the Catholic Church has never formally defined the existence of the devil or demons, but it's popular belief,” Rausch said. “It’s been part of the belief of Christians since the very beginning. So, many people believe it, others do not. I’m always fascinated myself, you know, I'm not sure I believe in angels and demons.”

How do you get an exorcism?

For someone who believes that demons exist and that one may have taken possession of their body, here’s how to go about getting an exorcism in the Catholic Church.   

The first step is to go to church and speak to a priest about the symptoms that are being experienced. The priest then may either say a prayer for deliverance or, if convinced of the presence of evil, seek help from the diocese. The diocese will assign someone to investigate and rule out natural explanation after consulting with physicians and mental health experts.

If the symptoms persist, a bishop decides if the church should perform an exorcism.

How often do exorcisms happen?

According to Rausch, exorcisms take place much more often in the Catholic Church on the big screen than in reality.

“I've never heard of one, actually,” Rausch said. “Most priests have never witnessed an exorcism, don’t know who the local exorcist is, if there is one. Most local churches or Diocese will have someone appointed to carry out exorcisms, but it’s not something that's frequently used in the life of the church.”

NBC LX spoke with three exorcists who not only have heard of exorcisms taking place, but have performed them. Exorcisms for demonic possession, they added, are extremely rare.   

How many exorcisms have been done?

Representatives of the Catholic Church told NBC LX they do not know how many exorcisms have been performed because the church does not keep numbers or records of such occurrences.

Diane Winston, professor in religion and journalism at the University of Southern California, said the church has a reluctance with exorcisms “because of the spectacular nature, the supernatural nature and the irrational nature.”

“The Roman Catholic Church, and I mean no disrespect, but it is basically an institution, its a hierarchy, it likes to keep things under control,” Winston said. “Exorcism is something you can’t control. It’s something they can’t explain. They’re not eager to publicize when these things happen because it just brings up a lot of questions that perhaps they can’t answer.”

Do exorcisms really work?

An exorcism is a form of psychotherapy that deals with the same types of human suffering, according to Dr. Stephen Diamond, a clinical and forensic psychologist and the author of "Anger, Madness and the Daimonic: The Psychological Genesis of Violence, Evil and Creativity.”

When an individual experiences possession syndrome, certain needs are not being met or are being repressed, Diamond said. The lack of those needs - whether emotional, spiritual or psychological – exert themselves through a form that appears to be a demonic possession but is actually just a metaphorical demon.   

“We don’t want to deal with or address, trauma, anger and rage,” Diamond said. “We tend to suppress it and clamp the lid down and then those feelings accrue over time the power take possession of us.”

Rausch said some forms of addiction can present themselves through a form of possession.

“We certainly have lots of examples of people who have been possessed, quote, by some kind of evil spirit,” he said. “Not necessarily a little demon with horns and a pitch fork, but whose whole personality has been taken over by evil.”

Well, if there is no demon to exorcise, how will an exorcism even help? Through the power of suggestion, Diamond said. A placebo for the possessed.

“Just by dint of the fact that someone believes in exorcism, for example, that in and of itself can be therapeutic for them,” Diamond said. “Problem is they have not really come to terms with their anger and what it’s about, instead they place it on the demon.”

Why are people fascinated with exorcisms?

When “The Exorcist” was released in theaters, it made nearly $240 million in domestic gross earnings at the box office. The roughly 40 movies about demonic possession that NBC LX found to have been released since have combined to gross over $1 billion domestically.

And the sequels keep coming, with “The Exorcist: Believer" expected to make roughly $30 million during its opening weekend.      

Call it a morbid curiosity, a supernatural fascination, a possession obsession.

“In all cultures, people seemingly believe that it’s possible for demons and devils and bad spirits to invade our bodies,” Winston said. “So, the idea that we, who think that we are the masters of our own fate and that we can control our lives, when we're confronted with the idea that something is inside of us possessing us, it's creepy and it’s exciting at the same time.”