In his early days as a stand-up comic, Bill Maher joked about being raised by a Jewish mother and Catholic father. He said he combined the two faiths by bringing a lawyer to confession.

"Bless me, Father, for I have sinned -- and I think you know Mr. Cohen," he quipped.

The host of HBO's "Real Time With Bill Maher" has been laughing at religion for a long time, skewering it as a bunch of ancient superstitions that do more harm than good. His barbed attitude toward Catholicism, Judaism, Mormonism, Islam and other organized religions is on display in "Religulous," billed as a "nonfiction film about the greatest fiction ever told."

"Religion is the ultimate taboo, and the one in most need of debunking," Maher, 52, said during a recent press conference at the Toronto International Film Festival, where the movie made its North American premiere.

In the documentary, made with "Borat" director Larry Charles, Maher travels the world looking for answers to his pointed questions about God and religion. He interviews born-again truckers in North Carolina, an actor playing Jesus at a Christian theme park in Florida, a renegade priest at the Vatican, an anti-Zionist Jew in New York, ex-Mormons in Utah, a Miami minister who claims he's the second coming of Christ, and two men at a Muslim gay bar in Amsterdam.

His conclusion? Religion is a "dangerous" crutch that defies rational thought, leads to wars and could be the spark that destroys the world.

"We need to grow up or die," he says in the film's closing scene in Megiddo, Israel, prophesied in the New Testament as the site of Armegeddon, the final battle between good and evil.

The film includes interviews with academics, scientists, authors, ministers and U.S. Sen. Mark Pryor of Arkansas, who voices doubt about evolution. Maher mocks the movement to teach the biblical story of creation along with evolution in schools -- a change supported by Republican vice presidential candidate Sarah Palin.

"That's an interesting approach, that we should teach stupidity alongside knowledge," said Maher, who was wearing a New York Yankees T-shirt with Hebrew lettering that he got in Jerusalem.

"It's like teaching magic and chemistry together," added Charles, sporting a ZZ Top beard and purple shoes.

Maher and Charles, 52, both had harsh words for politicians who "wear their religions on their sleeves."

"The U.S. has just gone through eight years of a Jesus-freak president, and people do believe the country was driven into a ditch," Maher said.

"Religulous," which Lions Gate will release in the U.S. on Oct. 3, uses some of the same ambush-interview techniques that made "Borat" so wildly popular. In one scene, an angry public-relations manager halts Maher's interview with a Jesus impersonator at the Holy Land Experience in Orlando, Fla., claiming the filmmakers were shooting without authorization.

"We were asked to leave almost every place we went to," Charles said.

Maher said he hopes the movie gets people to think about religion, though he's not sure how many minds it will change.

"We have no illusions," he said. "We know we're throwing rocks at a giant wall that's not going to come down in our lifetime."

- By Rick Warner / Bloomberg