Some Catholic viewers, particularly those who had lapsed in their faith but also including some priests, experienced spiritual crises. Many parishes reported callers inquiring about having an exorcism performed. The Rev. Richard Woods, a professor at Loyola of Chicago, said most of his calls were from lapsed Catholics for whom the film resurfaced their religious education prior to Vatican II. He said, "It stirs up memories of all those descriptions of hell that you got from nuns."
In 1975, The Journal of Nervous and Mental Disease published a paper by a psychiatrist documenting four cases of "cinematic neurosis" triggered by the film. In all he believed scenes depicting Regan's possession had surfaced a latent condition. He recommended physicians view the movie with the patient to help identify the sources of their trauma. Other external causes were suggested. One writer at Castle of Frankenstein took note of Friedkin's pride in the film's sound, which theaters played at maximum volume, and wondered if its low frequencies had induced or amplified patrons' anxiety.
Zinoman wrote four decades later: "The Exorcist ... was one of the rare horror movies that became part of the national conversation ... It was a movie you needed to have an opinion about." Journalists complained that coverage of the film was distracting the public from the ongoing Watergate scandal. Much of that coverage focused on the audience which, film historian William Paul wrote, "had become a spectacle equal to the film". He did not think any other film's audience received as much coverage as The Exorcist. The changes to the film's ending from the novel, Blatty agreed, might have made it harder to perceive that "the mystery of goodness" was the theme of the work. It appeared to him that for many viewers, including some of the America writers, the film ended with the demon triumphant through the deaths of the priests despite being exorcised from Regan. The ending of the novel made this clearer, but even in the film he saw Karras's suicide as a sacrificial act of love that reaffirmed his faith. a remark later characterized as Graham believing the print itself was possessed.