Dave Brubeck had a problem and, as a short concert intermission turned into a long and mysterious delay, the jazz master sheepishly came back on stage to make a confession.

It seemed that his son Chris had locked his electric bass in a dressing room and the Baylor University stage crew couldn't find the right key. Without that bass, the Two Generations of Brubeck ensemble -- pianist Brubeck backed by sons Chris on bass, Dan on drums and Darius on electric keyboards -- was in trouble.

"I really don't know what to do," said Brubeck, on that night in the mid-1970s.

High in the Waco Hall balcony, a voice called out: "Play the piano!"

Brubeck laughed and went to the keyboard. First he played some Bach, which evolved into gentle jazz improvisations that eventually turned into a stomping blues that roared on and on -- until Chris Brubeck finally had his bass.

Afterwards, Brubeck explained that, for him, music was music and he never could separate the many forms of music that he loved. In later interviews -- four in all, over three decades -- it became clear to me that his religious beliefs followed a similar path down the years.

Brubeck died of heart failure on Dec. 5, the day before he would have been 92.

As a composer, Brubeck was haunted by themes of justice and faith and, even during the glory years of the Dave Brubeck Quartet, he expressed his yearnings in explicitly religious classical works, often with lyrics written with his wife Iola. These compositions continued for the rest of this life.

"Really, I have trouble expressing myself about these things. I still do," he told me, during a 1984 interview that was published in the National Catholic Reporter. "Have you ever seen the notes in 'Light in the Wilderness'? ... I really said it all there. That still says what I believe -- although I guess no one's beliefs ever really stay the same.

"To me it all seems like the same journey."

In the liner notes for that 1968 recording, Brubeck wrote: "Although reared as a Presbyterian by a Christian Scientist mother who attended a Methodist church, and, although this piece was written with the theological counsel of a Vedanta leader, a Unitarian minister, an Episcopal bishop and several Jesuit priests, I am not affiliated with any church."

In particular, he cited the influence of "three Jewish teachers" -- philosopher Irving Goleman, classical composer Darius Milhaud and Jesus.

"This composition is, I suppose, simply one man's attempt to distill his own thought and to express in his own way the essence of Jesus' teaching," wrote Brubeck.

The soaring, chant-like theme from that oratorio's most famous piece, "Forty Days," became the hook for jazz improvisations in Brubeck concerts for decades to come. In the choral version, the verses cry out: "Forty days alone in the desert, days and nights of constant prayer, seeking in the wailing wind an answer to despair. Forty days of questioning: Why was he there, in the lonely desert? Forty days of fasting and prayer, searching for his destined role."

Eventually, Brubeck -- who had never been baptized as a child -- stunned his family by making the leap from his liberal Protestant background to Catholicism. The decision grew directly out of his experiences composing a Mass, completed in 1979, at the request of the Our Sunday Visitor publishing company.

Brubeck wrote "To Hope! A Celebration" in stages and, once it was complete, discovered that he had failed to write an "Our Father" anthem. During a family vacation in the Caribbean, he dreamed the entire missing piece -- jumping out of bed to sketch parts for chorus and orchestra.

The experience left Brubeck so shaken that he decided to be baptized as a Catholic, at Our Lady of Fatima parish in Wilton, Conn. While many insisted on calling him a convert, he always resisted that term and repeatedly explained that he found it impossible to describe precisely what he was "converting from" when he decided to enter Catholicism.

"You could say I was a lot of things or you could say I was nothing in particular" before becoming a Catholic, said Brubeck, the last time I interviewed him. "My wife and my kids didn't understand why I wanted to join the Catholic church. I'm not even sure I completely understood what happened. ... It was a calling."

Terry Mattingly is the director of the Washington Journalism Center at the Council for Christian Colleges and Universities and leads the GetReligion.org project to study religion and the news.

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