From a pastor-friend:

What's the most difficult thing about being a pastor?

McLaren's comment (that it's hard to be a Christian and a pastor) is a corollary to one I have expressed at different times: the danger of being in ministry is the assumption that you are always doing what God wants you to do - that being a 'professional minister' becomes too easily equated with 'doing the work of the Lord'. A major challenge is to keep these two in alignment and not always assume that they are. And, I suppose, a deeper question emerges when the two become incompatible or irreconcilable....