Before this year, Rick Warren, pastor of a Lake Forest, Calif., church, had already turned his congregation into one of the nation's five largest. He had already written a self-help book that has sold more than 30 million copies. He had already helped train hundreds of thousands of fellow pastors on how they could make their churches grow like his. But this year he propelled himself into even larger roles. He officially launched a wildly ambitious and well-funded plan to convince every Christian church on the planet to provide health care and economic-development services in its local area. And he became a political reporter, of sorts, serving as interlocutor for two of the most-watched interviews with John McCain and Barack Obama that took place in 2008. A purpose-driven life indeed.