Girl Meets God: On the Path to a Spiritual Life. By Lauren F. Winner. Algonquin Books, 305 pp., $23.95.

If there’s anything worse than books by writers in their mid-20s looking back on life, it’s books by people who have found Jesus. Unless you’re Augustine or John Donne, your spiritual autobiography, while doubtless thrilling to your parents, is probably going to sound trite. So Lauren Winner’s combination of genres—a memoir before its time, and a story about finding God—augurs to be deadly. But the author’s account of her odyssey from Orthodox Judaism to evangelical Christianity makes a vivid book.

Winner, 26, is a graduate of Columbia University and Clare College, Cambridge. She has been a staff writer for Christianity Today, book review editor for Beliefnet.com and a contributor to the New York Times Book Review. She is the coauthor of a new history of American Protestantism and is already working on her next book, a pastoral essay for unmarried Christians struggling with sexual temptation. She is an evangelical Episcopalian, prodigiously well read, who can talk scripture with the low-church folk and is well connected in the publishing precincts of the Ivy League.

Raised in North Carolina and Virginia by a Reform Jewish father and a lapsed Baptist mother, Winner turned in high school toward Orthodox Judaism. At Columbia, she wore ankle-length skirts and kept kosher. She dated a Harvard student, whom she peeked at, lovingly, across the mechitzah, the partition that separates the sexes during prayer.

Yet she found herself drawn to the Cloisters, the uptown New York museum filled with Christian art, where she spent hours staring at medieval unicorns. She took classes on the New Testament. When her boyfriend wondered about her new obsession, she said Christianity was just a hobby. But privately she remembered the teenage dream in which she had been kidnapped by mermaids and rescued by a man who resembled actor Daniel Day-Lewis but, she had always known, was Jesus.

Just before her senior year of college, Winner happened on Jan Karon’s novel At Home in Mitford; she spent the next week reading and rereading it and its sequel. “They were no great works of literature, just vignettes about the people in Father Tim’s parish, stories about ordinary Christians working out ordinary faith in their ordinary lives. They sang hymns I didn’t know from a prayer book I had never opened. And I thought, I want what they have.”

To a born-again Christian, this story will make perfect sense. The adolescent dream with a movie star Jesus, the charming if syrupy novels—these can be signs from God. To anyone who has not had such a conversion experience, these stories are a bit embarrassing. When Winner renounces her Judaism by abandoning her Jewish books on the steps of a synagogue, “the way an unmarried mother might have left her baby on the steps of an orphanage in some earlier era,” her religious life seems like a soap opera. As a spiritual memoir, her book is a failure in the ways that spiritual memoirs almost have to be: communion with God, like falling in love, is almost impossible to describe convincingly to the uninitiated.

As literature, however, the book succeeds. Although Winner sometimes swerves toward hokiness (after reuniting with an old flame, she takes “a shower that is long”; she is “courted by a very determined carpenter from Nazareth”), her prose mostly hums along. This book is an apt primer for anyone curious about Judaism, Jewish cooking, biblical exegesis, the mysteries of the Eucharist, and the Book of Common Prayer. You won’t forget her descriptions of the tart English woman who baptizes her, the Jewish friends hurt by her turn toward Christ, or her intimate relationship with the Jesus pictures covering her bedroom wall.

Winner doesn’t wimp out. She describes the four tattoos—forbidden by Jewish law—that she got as a teenager, and she owns up to her flaws: “My confessions seem usually to concern two familiar topics: prayer and sex. Not enough of one, too much of the other.” In Girl Meets God, we learn how a love for Jesus commingles with fishnet stockings, a taste for single malt scotch, and a guilty, wistful relationship with Judaism, the religion she has forsaken.

Girl Meets God left me still puzzled about Winner’s religious life, yet more intrigued than ever by her naked, brilliant eccentricity. That is the worst, and the best, I can say about this impressive book.