D. Keith Mano in 1971. (Jill Krementz)

D. Keith Mano, a onetime Shakespearean actor and self-described “Christian pornographer” who wrote provocative novels about the struggle for faith and who was a popular columnist for National Review, died Sept. 14 at a New York City hospital. He was 74.

He had complications from Parkinson’s disease, said his wife, Laurie Kennedy.

In the 1960s and 1970s, Mr. Mano (pronounced MANN-oh) was considered one of the country’s most promising young writers, publishing six novels in as many years, each filled with vivid writing and heady ideas.

He wrote from an avowedly conservative Christian perspective as a practicing Episcopalian before growing disenchanted and abandoning the faith, in part because he refused to take communion from a female priest. From 1972 to 1989, he also wrote a column of wide-ranging cultural commentary, “The Gimlet Eye,” for National Review, the conservative magazine founded by William F. Buckley Jr.

“Week in, week out, Mano was the best writer this, or any American magazine has had, for the last 50 years,” Richard Brookhiser, a senior editor of National Review, wrote in 2005.

Mr. Mano was long captivated by the battle between good and evil that is a central element of Christianity. He addressed weighty subjects such as war and peace, but he also wrote in explicit terms about sexuality, body functions, pornography, strip clubs and other subjects not typically featured in the Christian literary canon.

“I have the honor of being the one person that [Dr.] Ruth Westheimer says is too dirty for her to talk to,” he said in a 1994 interview with the now-defunct magazine the Wittenburg Door.

In Mr. Mano’s 1969 novel “Horn,” a pudgy white Episcopal priest is placed in all kinds of compromising positions while serving as the pastor of a predominantly African American church in Harlem during the height of the black power movement. In “The Proselytizer” (1972), Mr. Mano examined the hypocrisy of a sexually ravenous television evangelist in graphic detail.

The dystopian 1973 novel “The Bridge” is set largely in the 21st century, when environmental laws have forbidden killing of any kind — leading the human race into a form of voluntary suicide. (Reviewers for the New York Times and the Jesuit publication America both called it “repellent.”)

Mr. Mano spent nine years writing his next novel, “Take Five” (1982), a political and religious satire in which the 583 pages are numbered backward. During the course of the ambitious novel, the central character, a would-be filmmaker, loses all five of his senses.

Mr. Mano “seems to be trying to offend every race, color and creed,” critic John Leonard wrote in the Times. “It is as if James Joyce, for his sins, had been forced to grow up in Queens; as if Sam Beckett had been mugged by Godot in a Flushing comfort station; as if Sid Caesar played the part of Moby-Dick in a Roman Polanski movie shot underwater in Long Island City; as if Martin Heidegger had gone into vaudeville and . . . never mind. Just boggle.”

It was also, Leonard noted, “hilarious, even when it is vile.”

David Keith Mano was born Feb. 12, 1942, in New York. His father ran a family business, X-Pando Corp., which manufactures building materials.

As a student at Columbia University, Mr. Mano rebelled against what he saw as the prevailing secular liberalism of the intellectual world. After one class, he told the Columbia Daily Spectator in 1976, “I went over to St. Paul’s Chapel, and said, ‘If that’s the way the world is, I’d better turn to God.’ ”

After graduating in 1963, Mr. Mano studied at the University of Cambridge in England, where he began acting. He spent a year in the mid-1960s touring the United States with a Shakespearean theater company and worked for several years at his family’s company.

From 1968 to 1973, Mr. Mano published a novel each year, inviting comparison to Joyce Carol Oates and other rising literary stars of the time. After “Take Five,” he published only one other novel, “Topless,” in 1990. In that book, an Episcopal priest leaves his suburban church in Nebraska to take over a New York strip club managed by his brother, who has disappeared.

“My occupation hasn’t changed,” the priest says at one point, describing his relationship with the women in his employ. “I am still a pastor, still an authority figure. I still have a congregation that comes to me for advice. In fact, it’s the same stupid confessions, hassles, pretty much.”

From the 1960s to the 1990s, when he developed Parkinson’s disease, Mr. Mano attended almost every Columbia football game, home and away, even though the team seldom won a game. He sometimes tried to rally the hapless troops by reciting stirring passages from Shakespeare.

His first marriage, to Jo McArthur, ended in divorce. Survivors include his wife of 36 years, actress Laurie Kennedy, who had recurring roles in the TV series “Homicide: Life on the Street” and “Law & Order,” of New York; two sons from his first marriage; and four grandchildren.

Over the years, as a freelance journalist, Mr. Mano said he interviewed people who practiced incest and others who may have been cannibals. He underwent hypnosis, pretended to be an alcoholic, entered a mental institution as a patient and lived briefly as a cross-dresser.

For a classically trained actor with staunch religious beliefs — he eventually joined the Eastern Orthodox church — Mr. Mano adapted easily to the high-octane writing style of Playboy, Oui and other men’s magazines to which he often contributed.

“When your prose is in direct visual competition with soft, nubile young women all set for some antic hay,” he wrote, “you better talk loud, brother.”