He winces when he says it: "Some preachers preach past the point!" Andy Stanley's heritage is one of long sermons, but for his congregation at North Point Community Church in Alpharetta, Georgia, length doesn't equal depth—or impact.

What could most preachers do to make their sermons more powerful?

Teach less material at greater depth. Less is more. Instead of leaving listeners with a list of five things to remember—which they won't—plant one powerful thought. Most communicators make the same mistake: they have too much stuff. They miss their moment.

When I listen I often think, If you had just spent 30 minutes talking about that one thing, it would have been a great sermon.

I listened to a man speaking on marriage. His second point was brilliant. I was ready to get in the car with my wife, go home, and try it. But he had two more points after that. By the time he ended, nobody remembered point two. It was irritating because he had something to say, but it got lost in all the other stuff he ...