Composer Olivier Messiaen (1908-92) humbly reigned over modern classical music from the 1930s on, but as concert pianist Jacqueline Chew learned, he never neglected to express his reverence for the God of the Bible.

In 1944, Messiaen bequeathed Twenty Contemplations on the Infant Jesus to a torn, conflicted postwar world. This mammoth collage of musical extremes can sound as incomprehensible and lively as a child pounding a keyboard with unfettered glee, or as ageless and endless as a sober Zen Buddhist chant. It is still acclaimed as one of the peak piano compositions of this century.

When Chew first heard Contemplations, she felt an almost supernatural "calling" toward the music--an odd sensation for an atheist. Exploring Messiaen's influences, Chew studied Thomas Aquinas, Giotto's fourteenth-century frescoes, thirteenth-century Hindu rhythms, and the biographies of such Christian saints as Saint Terese of Lisieux. She began this labor of love as a skeptic, but eventually Messiaen's devotion won her over. "Little by little, I started believing," Chew remembers. "First I had responded purely to the music; eventually, the religious context became essential."

Memorizing from a score over a thousand pages long, Chew labored 11 years to master five of the twenty movements, including "The Kiss of the Infant Jesus" and "By Him All Things Are Made." In 1988 she pursued trilingual piano tutorials with Messiaen's wife, Yvonne Loriod, in Paris. Loriod was an invaluable guide to mysterious fingerings that allowed the pianist to coax out Messiaen's nuanced tonalities. Chew explains a cupped, rolling use of the small finger in a fashion that would be distinctly heretical to classical pianists.

Messiaen's notations for ...