The Church has warned the faithful of Satan’s dark power for over two millennia.

"Behind the disobedient choice of our first parents lurks a seductive voice, opposed to God, which makes them fall into death out of envy. Scripture and the Church's Tradition see in this being a fallen angel, called 'Satan' or the 'devil'," states the Catechism of the Catholic Church.

But in the early 1970s, when moral and cultural taboos were shattered, and the presence of evil in the world was reframed and rationalized as a problem for therapists rather than confessors, William Peter Blatty’s 1971 blockbuster, The Exorcist, told a different story.

Blatty died on Thursday at the age of 89. CNN reported that he had blood cancer and only learned about his condition last month. Julie Blatty, his wife of 33 years, confirmed that his death was caused by multiple myeloma.

Stephen King  tweeted:

RIP William Peter Blatty, who wrote the great horror novel of our time. So long, Old Bill.

I was a high-school student when the book, and later, the film adaptaion appeared. And my group of friends probably did  approach it primarily as a horror movie. But, as Catholics, we were also aware that the Devil was real.

Blatty constructed a chilling narrative of demonic possession based on a true story of a similar case that haunted his imagination for many years.  

In his fictional scenario, a young girl’s increasingly strange and violent behavior prompts her atheist mother to consult with medical experts. When they have no answers, she  turns to the Catholic Church.

A seasoned exorcist, Father Lankester Merrin,  is dispatched to the family’s home. There Blatty prepares the reader for a disturbing and ultimately violent confrontation between the forces of good and evil.

Another priest in the story, Father Karras, a Jesuit and psychiatrist grappling with his own spiritual doubts, is a placeholder for modern secularists.

Father Karras offers to explain the practical details of the case to Father Merrin, who politely dismisses the need for such information.

Prayer, fortitude, humility and enormous personal sacrifices are required, not medical assessments.

The older priest launches a spiritual assault that will free the young girl from the Devil, and set her mother on a spiritual journey toward Christ. It will also result in the deaths of the two priests, who give their lives to liberate the girl.

The New York Times’ obit  describes Blattty as “the foremost writer in a new hybrid genre: theological horror.” The paper also takes note of  the confused public response to the priests’ death as a win for the Devil, and Blatty’s own subsequent efforts to clarify the meaning of the tragedy with a new edit by the film's director, William Friedkin. 

“For years he pleaded his case to Mr. Friedkin, a longtime friend. In 2000, Mr. Friedkin relented, issuing a re-edited director’s cut of the film that made the triumph of Good over Evil more explicit.

“With the same purpose in mind, Mr. Blatty rewrote parts of the original book.”

The book carried secondary message about the redemptive value of suffering. And in 2011, when I interviewed Blatty at his Bethesda, Md., he explained this theme in some detail.

“Suffering is ultimately a mystery. But it has a lot to do with salvation,” said Blatty, who lost a beloved son.

“Try to imagine a universe in which there is neither suffering nor the possibility of suffering for any living creature.

“Could there be any virtue, courage, kindness? If you want to be steel, you have to go through a crucible; you can’t be handed spiritual food stamps. Christ on the cross showed us how to do it.”

“In The Exorcist, the prime example of the mystery of suffering would be the mother, who is an atheist. What leads this woman to a Jesuit priest?”

Likewise, the Catechism explains the following:

"Although Satan may act in the world out of hatred for God and his kingdom in Christ Jesus, and although his action may cause grave injuries - of a spiritual nature and, indirectly, even of a physical nature- to each man and to society, the action is permitted by divine providence which with strength and gentleness guides human and cosmic history. It is a great mystery that providence should permit diabolical activity, but 'we know that in everything God works for good with those who love him.'"

During our conversation, Blatty had much to say about the reported rise in demonic possessions, even as Catholics in the West continue to shrug off Satan as a bogeyman from a another age.

“I have a number of explanations for the increase in possession in the Western world. You have to begin by examining how an alien intelligence or demon takes control of the organism of a human being,”  he observed.

“The personality of the victim must be shattered, so there can be an opening.

“What can create that opening? Drugs, certainly.”

In the book, however, the young girl provides an opening to  demonic forces by playing with an Ouija board. Thus, readers who cared to notice were warned that engaging in the occult (In Latin, defined as "knowledge of the hidden") was dangerous.

Indeed, the Church has directed the faithful to avoid any kind of practices designed to predict or control the future, or, more directly, to access the power of Satan for any purpose whatsoever.   Three decades ago, when I interviewed the chief exorcist of Rome, he emphasized that Revelation has supplied us with all the information we need to conteplate the future, one in which Jesus Christ will ultimately triumph over the Devil.  

The film adaption of The Exorcist raised these same questions. And while some audiences focused on the frightening special effects, the physical agony of the young girl testified to the truth that the Father of Lies will enslave, not empower human beings.

Last year, Friedkin, who has described himself as anagostic, took up the issue of demonic possession in an article for Vanity Fair. He included an eyewitness account of an exorcism in Italy that had been videotaped with the permission of the exorcist, and he also featured the fascinating responses of medical experts to the victim's behavior during the videotaped ritual.

Decades after he worked on the set of The Exorcist, Friedkin, like so many  people, was still captivated by Blatty’s story, and still pondering its deeper meaning.

Blatty remained a devout Catholic to the end. And while he gained success and recogntion in Hollywood, I sensed, during our meeting, that the longterm spiritual and catechetical impact of The Exorcist mattered much more to him than the Oscar he won for Best Screenplay for his film adaption.

May he rest in peace, and may we thank him for his unique success in educating the faithful and the larger public on the brutal reality of Satan in our world.