Daniel C. Dennett in the Washington Post:
Here are some questions that have haunted me for years. How many preachers actually believe what they say from the pulpit? We know that every year some clergy abandon their calling, no longer able to execute their duties with conviction. This can never be a decision taken lightly, and many of them labored on for years before taking the leap. Are they the tip of an iceberg? Is there a problem of deep hypocrisy separating many pastors from their flocks? What is it like to be a non-believing preacher? How do they reconcile their private skepticism with the obligations of their position? And how did they get into their predicament?
Several years ago I set out to get some answers, in collaboration with Linda LaScola, a clinical social worker with years of experience as a qualitative researcher. I had told her of my interviews with deeply religious people while writing my book, “Breaking the Spell” (2006), and of my surprise at how many of them were eager to tell me, in confidence, that they didn't believe a word of the doctrines of the faith to which they were devoting their lives. Was this also true of ordained clergy? With some help from me and a network of advisers, LaScola identified some brave informants, all currently Protestant pastors with congregations, and interviewed them at length and in depth–and of course in deep confidence.
More here. Also read “Preachers who are not Believers,” a study by Daniel C. Dennett and Linda LaScola of the Center for Cognitive Studies at Tufts University.