How Exorcism Works

By: Julia Layton  | 
Is this really what a priest looks like during an exorcism? D-Keine / Getty Images

If you've seen the 1973 movie "The Exorcist," you at least have some idea of what exorcism is about. It has to do with ridding a human being of diabolic possession, it's typically associated with Roman Catholic beliefs, and if the movie is any indication, it's very, very scary. You may remember with a shudder the teenage girl whose head spun around, her body in convulsions, her voice that of a demon spewing curses and obscenities while the battered priest of "The Exorcist" fought the devil to save her soul.

This Hollywood version of an exorcism is supposedly based on a real-life exorcism performed on a Maryland boy in 1949. Priests are still performing exorcisms today.


Is exorcism real, or are the subject and the exorcist unconsciously acting out roles from a popular movie? Are there other explanations for what some people call "possession"? In this article, we'll focus on the Roman Catholic exorcism rite because of its tremendous presence in popular culture, thanks to "The Exorcist" and its successors. We'll learn why a priest might perform an exorcism, find out what the ritual involves, take a look at a real-life exorcism and discuss the controversy surrounding the practice.

What is Exorcism?

The Catholic Encyclopedia defines exorcism as "the act of driving out, or warding off, demons or evil spirits, from persons, places, or things, which are believed to be possessed or infested by them, or are liable to become victims or instruments of their malice." In short, it is a ritual performed by a Catholic priest to expel the devil from a person, place or thing.

There are several types of exorcism in the spiritual practice of the Roman Catholic Church:

  • Baptismal exorcism: blessing an infant prior to baptism to cleanse it of evil resulting from original sin
  • Simple exorcism: blessing a place or thing to rid it of demonic influence
  • Real exorcism: performing the Rite of Exorcism to rid a human being of diabolical possession

A "real exorcism" is what most of us think of when we think of exorcism. In this case, the priest-exorcist is dealing with a human being who is possessed by the devil — the devil is inhabiting this person's body.

Scene from "The Exorcism of Emily Rose" (2005)
Photo courtesy Sony Pictures

According to the Church, telltale signs of demonic possession include [ref]:

  • Speaking or understanding languages which the person has never learned (different from "speaking in tongues," which is considered a sign of religious ecstasy, not possession)
  • Knowing (and revealing) things the person has no earthly way of knowing
  • Physical strength beyond the person's natural physical makeup
  • A violent aversion to God, the Virgin Mary, the cross and other images of Catholic faith

If you do a Google search for the word "exorcism," you'll find ads for exorcists — Wanda Pratnicka, for example, claims to have "30 years experience with 25,000 successfully performed exorcisms." This makes demonic possession seem like a pretty common occurrence.

But to the Roman Catholic Church, it's rare: It only finds true demonic possession in about one out of every 5,000 reported cases [ref]. So what does it take for the Church to send in an exorcist?


The Investigation: Possessed?

Possession and exorcism date back to ancient times, possibly beginning with early shamanistic beliefs in which spirits of the dead could do harm to the living. Shamans would enter a trance state to find the troublemaking soul and discover from it the way to end the victim's pain.

In ancient Egyptian and Babylonian cultures, illnesses and other afflictions were regularly attributed to evil spirits that invaded the human body, and priest-healers carried out intricate ceremonies to cause the evil spirits to leave.


Today, when someone reports a possible case of possession to the Church, an investigation begins.

Father Benedict Groeschel, a Franciscan priest who holds a Ph.D. in psychology from Columbia University, was the man the Archdiocese of New York called on to investigate cases of apparent possession that landed on its desk in the '70s and '80s. In "American Exorcism," he describes his experience this way (Cuneo 22):

... when cases were referred to me I usually sought the help of a laywoman in the archdiocese who possessed a gift for discerning spirits. In her view, and also mine, none of the people I brought to her were victims of possession; none of them, in other words, were in need of formal exorcism. But that doesn't mean they weren't being afflicted or oppressed in various ways by demonic forces. Demonic oppression is much less serious than full-scale possession, and it can usually be dealt with by what we refer to as a simple prayer of deliverance.

A typical investigation is essentially a process of elimination: Does the subject exhibit the telltale signs of possession by supernatural forces? Is there any other way to explain the subject's behavior besides demonic possession?

Often, the priest will consult a mental health professional in his investigation in order to determine whether the "possessed" person's symptoms can be fully explained by mental illness.

According to Michael Cuneo's "American Exorcism," there are about a dozen psychiatrists in the United States who evaluate potentially possessed subjects for the Catholic Church. The subject will also undergo a medical examination to find out if the symptoms can be attributed to a physical disorder or illness. The priest may consult a Church-approved expert on the paranormal for additional input. Another possibility the investigator must consider is plain old fraud.

If the priest is convinced of the validity of the possession and that an exorcism is the appropriate way to help this person, he will report back to his supervisor (in most cases, the diocesan bishop) that an exorcism is in order. The Church may then decide to sanction an official exorcism and appoint an exorcist to the case.


The Exorcist

Appointing an Exorcist

If the Church decides it has a truly possessed individual on its hands — one that requires an exorcism — the next step is to appoint an exorcist to the case. This is often the same priest who performed the investigation, but not always.

Casting out the devil is not part of a typical priest's daily duties. Most priests have never performed an exorcism. But some have.


Official numbers are hard to come by, but "American Exorcism" reports that in 1996, the Catholic Church appointed 10 priests to the position of exorcist in the United States, bringing the total number to 11.

Cuneo estimates the worldwide number at somewhere between 150 and 300, while other reports claim there are 300 to 400 official exorcists in Italy alone. There are also priests who are not official exorcists but claim to have permission from their Catholic bishops to perform exorcisms at their discretion.

Training and Execution of Exorcism

The exorcism ritual has made a big comeback from being nearly extinct throughout most of the 20th century.

Traditionally, Catholic exorcists undergo very little specific training to aid them in their job. While they learn a great deal about the devil and the risks and manifestations of evil, exorcism itself is not a specialized area of study in seminary school. What they know, they know from their experience in the role of priest and from the Roman Catholic rite of exorcism, which is the official document detailing the prayers and steps of an exorcism.

Things are starting to change, though.

Official exorcists of the Catholic Church formed their own organization in 1992. The International Association of Exorcists holds biannual meetings in Rome and sends out a quarterly newsletter to its members. In the newsletter, exorcists tell of particularly difficult or interesting cases and swap "tricks of the trade" (Cuneo, 266). In addition, in 2005, Rome's Regina Apostolorum Pontifical Academy (a university connected to the Vatican) started offering a class on exorcism.

Once the Church appoints one of its official exorcists to perform the ritual, the next step is to get the devil to leave the person's body.


The Exorcism

"Father Moore" dressed in surplice and purple stole in "The Exorcism of Emily Rose"
Photo courtesy Sony Pictures
The Vatican's Revised Exorcism Rite

In January 1999, the Vatican issued a revised exorcism rite to be used by Catholic priests. The directions for conducting an exorcism comprise a single section in the Roman Ritual (Rituale Romanum), one of the books describing the official rites of the Roman Catholic Church. Prior to 1999, the official exorcism rite dated back to 1614.

To perform the rite, the exorcist dresses in his surplice and purple stole. The ritual of exorcism is mostly a series of prayers, statements and appeals.


These prayers are loosely broken down into the "imploring formula," in which the priest asks the Holy Spirit to free the subject from the devil ("God, whose nature is ever merciful and forgiving, accept our prayer that this servant of yours, bound by the fetters of sin, may be pardoned by your loving kindness"), and the "imperative formula," in which the priest demands in the name of God that the devil leave the subject's body ("Depart, then, impious one, depart, accursed one, depart with all your deceits, for God has willed that man should be His temple").

To read the entire 1999 revised rite, see Catholic Doors Ministry: 1999 Rite of Exorcism.

In addition to these recitations, the priest takes certain actions at particular times during the rite: He sprinkles holy water on everyone in the room, lays his hands on the subject, makes the sign of the cross both on himself and on the subject and touches the subject with a Catholic relic (usually an object associated with a saint).

Malachi Martin's Perspective on Exorcism

Malachi Martin, a former Jesuit priest and self-proclaimed (but not official) exorcist, offers additional information on exorcism — information not endorsed by the Church. A controversial figure in the Catholic world, Martin reveals in the book "Hostage to the Devil" what he considers to be the typical stages of an exorcism (Cuneo 19-20):

  1. Pretense: The demon is hiding its true identity.
  2. Breakpoint: The demon reveals itself.
  3. Clash: The exorcist and the demon fight for the soul of the possessed.
  4. Expulsion: If the exorcist wins the battle, the expelled demon leaves the body of the possessed.

"Hostage to the Devil" created quite a stir in the Church. The book details supposedly factual exorcisms that Martin claims to have performed, assisted with or witnessed. The exorcisms Martin describes are on the level with "The Exorcism" in terms of action and violence.

Believers criticize the book, thinking Martin has sensationalized and therefore belittled the power of the devil. But if Martin's vivid scenes don't ring true to the Church and its supporters, what does a real exorcism look like?


A Real-life Exorcism

Michael Cuneo's Observations

In researching "American Exorcism: Expelling Demons in the Land of Plenty," Michael Cuneo, a sociology professor at Fordham University, attended all sorts of exorcisms. One official, Church-sanctioned exorcism that Cuneo sat in on involved a man he calls Warren (the possessed) and a priest-exorcist he calls Father Peter.

Warren's life is painful to him — he is a heavy drinker, regularly has sex with people he has just met and is generally depressed. He has recently begun to hear voices, see things and feel an "unbearable pressure" on his body at night.


In short, Warren is tormented.

His local pastor contacted Father Peter's supervisor, and with the agreement of a psychiatrist, they arranged an exorcism. The following details of a real-life, official exorcism are taken from "American Exorcism" (243-245). While Cuneo does not provide a date, this exorcism most likely took place before the 1999 revisions to the rite.

The Exorcism of Warren

In the basement of an unremarkable building in the Midwest, Father Peter, in his surplice and purple stole, stands directly in front of Warren, who sits in a chair with his head bowed and his fists clenched. Cuneo sits off to the side. Father Peter begins the ritual:

"All-powerful God, pardon all the sins of your unworthy servant. Give me constant faith and power so that, armed with the power of Your holy strength, I can attack this cruel evil spirit in confidence and security..."

While speaking these initial words, the priest sprinkles Warren, Michael Cuneo and himself with holy water.

Father Peter moves closer to Warren, makes the sign of the cross and lays his palm on Warren's forehead. Warren sits perfectly still while Father Peter recites the prayers of the exorcism ritual. Father Peter appeals to Christ, the Virgin Mary and the saints to aid him in his endeavor to save Warren's soul. Warren remains silent.

"I exorcise you, Most Unclean Spirit! All Spirits! Every one of you! In the name of Our Lord Jesus Christ: Be uprooted and expelled from this Creature of God..."

Father Peter makes the sign of the cross on Warren's forehead, presses a relic against his chest and ultimately finishes the exorcism with:

"Go away, Seducer! The desert is your home. The serpent is your dwelling. Be humiliated and cast down. For even though you have deceived men, you cannot make a mockery of God ... He has prepared Hell for you and your angels."

Father Peter then leads Warren in a few closing prayers and additional readings. He asks Warren how he feels. Cuneo relays Warren's answer: "'Peaceful,' Warren said, but also a bit confused. He thought he'd felt something leaving him during the exorcism, but he wasn't sure."

It's not exactly "The Exorcist," but then, that's a pretty tough act to follow.

According to Cardinal Medina, "[Possession] has sensational features, in which the devil in a certain way takes over the physical powers of the possessed person. However, the devil cannot control the subject's free will and thus cannot cause him to sin. Still, the physical violence the devil exerts over the [possessed] person is an inducement to sin and this is what he seeks."

Was Warren genuinely possessed? Did Father Peter get the devil to leave Warren's body? There are those who believe, and there are those who don't. But no one got hurt, and it may just be that Warren is better off having undergone the exorcism. So some might wonder, what's the problem?


The Controversy

The battle surrounding exorcisms exists mainly on two related fronts: the huge "exorcism for profit" ministries that have sprung up in the last couple of decades and the "psychology versus religion" debate that sprang up with the advent of psychiatry in the 1800s.

Exorcism for Profit

As soon as money enters the picture, the skeptics are going to win some ground. The rise of money-making "exorcism ministries" around the world leads many people who might otherwise reserve judgment to outright reject the validity of the Catholic view of possession and exorcism, even though the exorcisms performed by these unofficial exorcists are not in any way connected to the Catholic Church.


A particularly popular exorcism ministry in the United States, Bob Larson Ministries, televises its weekly conferences. In these mass exorcisms, for which large groups can receive a "family rate" on tickets, Mr. Larson exorcises the demons of an auditorium full of people. Financial donations on top of the ticket price are not required for his services, but they are welcome.

There are always people who will point to profit as evidence of an ulterior motive, especially when you mix profit with the paranormal.

Psychology vs. Religion

Where one person sees possession and pulls out his rite of exorcism, another sees mental illness and pulls out the DSM V. This is probably the greatest debate surrounding the practice of major exorcism: there may be earthly explanations for behavior the Church considers evidence of diabolical possession.

Several psychological disorders, including Tourette syndrome and schizophrenia, can produce the types of effects seen in "possessed" people.

  • People with epilepsy can suddenly go into convulsions when having a seizure.
  • Tourette syndrome causes involuntary movements and vocal outbursts.
  • Schizophrenia involves auditory and visual hallucinations, paranoia, delusions and sometimes violent behavior.
  • Psychological issues like low self-esteem and narcissism can cause a person to act out the role of "possessed person" in order to gain attention.

In a case where the subject is in fact suffering from mental illness, the Church is doing harm by labeling the person possessed if this prevents the person from seeking out the medical treatment they require.

Cardinal Jorge Arturo Medina Estevez, introducing the New Rite for Exorcisms to the press in 1999, responds to the conflict this way:

... exorcism is one thing, and psychoanalysis is another. If the exorcist has any doubt about the mental health of the possessed, he should consult an expert ... It often happens that simple people confuse somatic problems with diabolical influence, but not everything can be attributed to the devil.

The ultimate question remains: "Does exorcism help people or harm people?" It is difficult to come by documentation of any outcomes of official Roman Catholic exorcisms, harmful or beneficial.

This is by design. According to the official rite, exorcisms are supposed to be low-key — not necessarily secret, but not performed in public or in front of press representatives — so that the ritual does not become a "show." Results are not to be published, whether the exorcism is a success or a failure.

There is considerable documentation, however, of the harmful outcomes of exorcisms performed outside the Catholic Church. One widely reported incident took place in June 2005 in Tanacu, Romania.

A priest and several nuns in a Romanian Orthodox convent believed that Maricia Irina Cornici, a 23-year-old nun who lived in the convent, was possessed. So they carried out an exorcism ritual: They tied her to a cross, pushed a towel into her mouth and left her alone without food and water. The intent was to drive out the demon inhabiting her body.

Cornici died after three days. Officials believe the young woman had schizophrenia.


Exorcism in Popular Culture

Hollywood alone has produced a number of films depicting exorcism, including (but by no means limited to) the following:


Lots More Information

Related HowStuffWorks Articles
More Great Links

  • "Cardinal Medina on New Rite for Exorcisms." ZENIT News Agency - The World Seen From Rome, January 26, 1999.
  • "Crucified nun dies in 'exorcism.'" June 18, 2005.
  • Cuneo, Michael W. "American Exorcism: Expelling Demons in the Land of Plenty." Doubleday. New York, 2001.
  • "Exorcism Rite Reformed." Catholic Culture.
  • "Exorcism."
  • "Exorcism." New Advent Catholic Encyclopedia.
  • "Exorcism." The Skeptic's Dictionary.
  • "Jinn Comrade (Qareen): How to Get Rid of It?" Islam Online.
  • "Priests Sign up for Exorcism 101." February 18, 2005. Reprinted by The Tibetan Foundation.
  • "Vatican issues first new exorcism ritual since 1614." January 26, 1999.
  • "Vatican U. Offers Exorcism 101." February 17, 2005.
  • "What is Tourette Syndrome?" Tourette Syndrome Association.