The first book I read by him was during my preparations for my ordination selection panel and is called The Contemplative Pastor. I have since read almost everything he has written. I think he is challenging to many because in a church so often characterized by a need to put people in boxes he won't let you put him in one. How frustrating for us.
Peterson loves poetry, novels, art, food, nature, John Calvin and seems to dislike powerpoint, conferences, leaders, personalities and contemporary worship songs. The clue to him might be the word he chose for his five books on theology-'Conversation'. So, to read and understand Peterson you probably need to like and enjoy a conversation. So many who profess an interest and passion for God seem to not like this word at all nor its practice. It is a word that requires us all to be vulnerable and to realize that we might have something more we need to learn.
Peterson is getting some interest because a young, go-getting US mega-church pastor of the Village (6000 and growing) called Matt Chandler quoted him in a talk. This talk was possibly given to an audience full of those sound non-conversational types who are exactly the crowd who tut at the mere mention of the Message. (Some of my dear friends tut so I say this with a smile)
The IMonk has explored this at length and I share the view that to do ministry without having read Working the Angles from which Chandler quotes will be the poorer for the neglect. I agree with him that Chandler is an inspiring man who seems to know his own mind. He also seems to get and preach the gospel as illustrated below.
Recently Chandler was interviewed and it is a very helpful six minutes and tells you a bit about what makes him tick and listen out for the Peter Drucker quote. If you want one for the ipod I recommend this.
Finally, if you have never come across Peterson here he is as you might have expected-in conversation.