It's not easy to make the Church at Brook Hills, Alabama's second-largest congregation, look like a slum. But in 2010, the church collected trash all over Birmingham and set its stage in corrugated metal, scrap wood, plastic tarps, and other detritus. Three months before, their lead pastor, David Platt, had proposed that their church "take India," by which he meant pay for Compassion International's child survival programs in the country for an entire year. The whole church couldn't jet off to India, but the rubbish on stage tangibly reminded its members of the country's impoverished communities.

With the stage literally set, Platt called his church to something more than giving $525,000 to Compassion. Platt and the Church at Brook Hills (affiliated with the Southern Baptist Convention) spent a full year praying for the world, reading the entire Bible, giving their money to those in need, spending time in a context beyond Birmingham, and building community.

The five components of "the Radical Experiment" may not seem that radical; they're more like basic Christian discipleship. But they struck a nerve at the church and beyond. Forty families and singles committed to moving into a disadvantaged area of Birmingham. As one attendee told me, the news created something of a reputation for the church. "People still ask me," she said, "whether I go to that church where people are moving into the most dangerous parts of Birmingham." And the message spread well beyond the city of 1 million. After Platt released Radical in May 2010, it spent more than two years on The New York Times advice best-seller list. Three years later, it's still on CBA'S (formerly ...

1