In case you don't know, Tim Keller is a pastor in Manhattan who is the smartest guy... well, in a really big set. Put it this way: everything he says is the smartest thing I've ever heard a pastor say. Or somewhere near that. He's really smart! And I'll put him up against anyone else's smart guys any day. He can eat Hitchens and Dawkins for breakfast (not hard to do).
Must stop gushing. Here's the video: