It happened at the moment in U2's Zoo TV show where Bono did his "Elvis-devil dance," decked out in a glittering gold Las Vegas lounge suit and tacky red horns.

As usual, the charismatic singer pulled some girl out of the crowd to cavort with Mister MacPhisto, this devilish alter ego. On this night in Wales, his dance partner had her own agenda, Bono told the Irish Times.

"Are you still a believer?", she asked. "If so, what are you doing dressed up as the devil?"

Bono gave her a serious answer, as the music roared on. "Have you read 'The Screwtape Letters,' a book by C.S. Lewis that a lot of intense Christians are plugged into? They are letters from the devil. That's where I got the whole philosophy of mock-the-devil-and-he-will-flee-from-you," replied Bono, referring to U2's ironic, video-drenched tours in the 1990s.

Yes, the girl said, she had read "The Screwtape Letters." She understood that Lewis had turned sin inside out in order to make a case for faith.

"Then you know what I am doing," said Bono.

It's highly unlikely Mister MacPhisto will make an appearance when U2 rocks the Super Bowl XXXVI halftime show. During their recent "Elevation" tour, U2 performed on a stage shaped like a heart and Bono opened the shows by kneeling in prayer. He began the anthem "Where the Streets Have No Name" by quoting from Psalm 116 and shows ended with shouts of "Praise! Unto the Almighty!"

But whatever happens Sunday in New Orleans, U2's presence almost guarantees that people will dissect it in church coffee hours as well as at watercoolers. Plenty of believers remain convinced Bono's devil suit was more than symbolic.

"I think they have been clear -- for nearly 25 years now -- about the role that Christian faith plays in their music. They're not hiding anything,"said the Rev. Steve Stockman, the Presbyterian chaplain at Queen's University in Belfast, Northern Ireland. He is the author of "Walk On: The Spiritual Journey of U2" and hosts BBC's "Rhythm and Soul" radio program.

"At the same time, they have always left big spiritual questions hanging out there -- unanswered. That is an interesting way to talk about art and that's an interesting way to live out your faith, especially when you're trying to do it in front of millions of people."

Stockman has never met the band. Still, there is no shortage of source material since Bono, in particular, has never been able to keep his mouth shut when it comes to sin, grace, temptation, damnation, salvation, revelation or the general state of the universe. Two others -- drummer Larry Mullen, Jr., and guitarist Dave "The Edge" Evans -- have long identified themselves as Christians. Bassist Adam Clayton remains a spiritual free agent.

The key, said Stockman, is that U2 emerged in Dublin, Ireland, in a culturally Catholic land in which it was impossible to be sucked into an evangelical subculture of "Christian news," "Christian radio" and "Christian music." The tiny number of Protestants prevented the creation of a "Christian" marketplace.

Thus, U2 plunged into real rock 'n' roll because that was the only game in town. U2 didn't collide with the world of "Contemporary Christian Music" until its first American tours. Then all hell broke loose.

While the secular press rarely ridicules the band's faith, noted Stockman, the "Christian press and Christians in general have been the doubters" who were keen to "denounce the band's Christian members as lost." Many have heaped "condemnation on their lifestyles, which include smoking cigars, drinking Jack Daniels and using language that is not common currency at Southern Baptist conventions."

It's crucial that most U2 controversies center on lifestyle issues. But Stockman is convinced that deeper divisions center on what Bono and company are saying -- in word and deed -- about the church's retreat from art, media and popular culture.

The contemporary church "has put a spiritual hierarchy on jobs," said Stockman. "Ministers and missionaries are on top, then perhaps doctors and nurses come next and so on to the bottom, where artists appear. Artists of whatever kind have to compromise everything to entertain. Art is fluffy froth that is no good in the Kingdom of God. What nonsense."