At the blog Epiphenom, the author of this post reviews recent research into the issues associated with the treatment of delusions containing religious elements. The original article, by Sylvia Mohr and others (University Hospital in Geneva, Switzerland), examined the particular benefits and challenges of working with clients who experience delusions with religious themes. Briefly, delusions, are erroneous beliefs that involve a misrepresentation of perceptions or experiences (as defined in the DSM-IV-TR). Delusions can encompass a variety of themes, with religion being one type. Delusions are a psychotic symptom, and as such, they indicate a break from reality; that is, one is not delusional if he or she is simply mistaken about something. Delusions are a belief system , usually centered on a theme, that involves a distortion of reality. Often, delusional beliefs are theoretically possible, but not grounded in actuality. For example, an individual may believe the CIA has targeted him for assassination, due to some special feature he believes he possesses (certain knowledge, etc.). Could the CIA do this, theoretically? Sure. Are they? Generally, no. Bizarre delusions, on the other hand, are beyond possibility: for example, the belief all of your organs have turned to stone. In this case, not possible. It is helpful to consider these types of beliefs on a continuum, because there can be gray areas - where does suspiciousness end, and paranoia begin? When does something go from far-fetched to impossible? These can be tricky questions, and they often require exploration.
Anyway, back to the original point. Religious delusions often center around a belief one has some special relationship with a religious figure (often God, but also others, such as angels or demons). More extreme beliefs include a belief one is a major historical figure. The link above explores why in some cases, the nature of a religious delusion provides comfort in a way other delusional themes do not, but also why religious delusions may inhibit treatment more than other types of delusions.
As I've posted before (I think), delusions can be difficult to treat. In the case of a delusional disorder (generally absent any other psychotic symptoms, such as disorganization, hallucinations, etc.), an individual will rarely seek out treatment voluntarily, and will typically refuse medication. If the delusion is part of a Schizophrenic presentation, it is the delusion that is often the most resistant to treatment. The delusional beliefs will be the last to respond to medication, and take the longest to abate. When one considers the nature of a delusion, this is understandable. You are basically asking someone to stop believing what they think they know.
Heck, have you ever argued politics with someone? People rarely give up on beliefs, and if they do, it is generally of their own accord, not because someone else told them they are wrong. Imagine if, starting today, everyone began telling you the sky was green. You look outside, and it's still blue. But, everyone else says it's green, and they start to criticize you, patronize you, recommend you get your eyes checked, etc. What would you think? This is the perception of an individual suffering from a delusion - to them, the evidence is clear, and you are the one who is wrong. To the extent research like this further aids in identifying specific isues and recommendations for various types of symptoms, rather than a one-size approach, the better our interventions will become. Read the whole thing.