The Smart Shepherd

Place: New York City. Time: 9 o'clock on a Sunday morning. It's fair to say that many, if not most, of the inhabitants of Manhattan —mostly single, professional, well educated and young—are sleeping it off somewhere. Half of America has roused itself by now and is heading off to church, but in the city that never sleeps, the Sabbath is a time for slumber.

There's an exception. On a sun-splashed corner near Central Park a churchlike building is filled to the rafters with Christian worshipers. By 9:15, the room is at capacity. By 9:20, even the balcony is full. There's nothing sexy here. There's no rock band, no drop-down theater-size video screen, no 100-member gospel choir—just a few chamber musicians and a couple of prayer leaders to help the congregation along in its hymns. The crowd at Redeemer Presbyterian is overwhelmingly young, single, professional and—for lack of a better word—sober.

Don't let your mind drift, or you will miss the main attraction. At 9:40, the voice you hear reading from the Scriptures changes suddenly; it becomes deeper, more authoritative and coarser, with traces of Pennsylvania and Georgia in the vowels. Look up. The callow junior minister has disappeared. Standing at the microphone is a man more than six feet tall with a shiny bald head and wire-rim spectacles, looking more like a college professor than a megachurch pastor. This is the Rev. Tim Keller, a Manhattan institution, one of those open urban secrets, like your favorite dim sum place, with a following so ardent and so fast-growing that he has never thought to advertise. He rarely speaks to the press.

His reticence, though, is about to belong to the past. With the publication this week of his first book, "The Reason for God," Keller, who is 57, is in the midst of a dramatic change in direction. Once highly protective of his community's grass-roots approach to growth—tell a friend, bring a friend—Keller is now pitching himself as a C. S. Lewis for the 21st century, a high-profile Christian apologist who can make orthodox belief not just palatable but necessary. To complement this role, Keller is also reaching out to young, urban Christians around the world, offering to help them build churches like his. To put it bluntly, Keller wants to be the Rick Warren of global cities. "It's hard to say this without sounding snobby," says Keller in an interview, "but some of what we do at Redeemer, we feel would be good everywhere … We want to, as humbly as we possibly can, renew churches."

Keller started Redeemer 17 years ago in a small rented church on Manhattan's Upper East Side. Now he preaches five times on Sundays, shuttling between three different rented venues and reaching more than 5,000 people each week (5,000 also download his sermon online). A recent sermon is taken from the Book of Job, and its message is unrelentingly grim. There's no pat "I'm OK, you're OK" theology here. Peppering his discussion with quotations from The New York Times Book Review and the British moral philosopher Alasdair MacIntyre, Keller promises that human suffering is inexplicable and that it will break you. "Basically," he says later, "the idea is, you can't manage your suffering and you shouldn't manage your suffering, and that's one of the values of it." Keller is a pastor for people who like their Christianity straight up.

"The Reason for God" is a high-minded argument against recent popular atheist tracts like Christopher Hitchens's "God Is Not Great." The book is demanding, but ultimately it disappoints because its pages lack the charisma and conviction so evident in the man. More successful, perhaps, are Keller's mentoring efforts.

He is helping other pastors use his "formula," if you can call it that—orthodox Christianity and challenging preaching, with an emphasis on social justice and community service—in cities like Amsterdam, São Paolo, Berlin and Paris. Keller believes that young urban people too often face an unsatisfactory choice: the dispassionate formality of the established churches or the fire and brimstone of the conservative evangelicals.

Like so many New Yorkers, Keller is a misfit. He's a megachurch pastor who doesn't like megachurches. He's an orthodox Christian who believes in evolution. He emulates the Puritan preacher Jonathan Edwards and loves a good restaurant. He's an evangelist who relishes the power of doubt. New York is the perfect home for such an idiosyncratic Christian: "I'm probably an overeducated guy who makes things too complicated for a lot of people," he says. As it is for all New Yorkers, the question for Keller is whether he—or his vision—will ever be at home anywhere else.