GMgerrymander wrote:

This is interesting to play with.  Especially if the players are unaware of the reality...

I think, in order for this to be an effective game device, it is important that players are unaware. It would probably work best if the various priesthoods had ranks that, once achieved, a little more knowledge is granted to the promoted initiate; a little like Freemasons I guess (not trying to be inflammatory by saying that). I guess the relevant Rank in the chosen priest profession would help determine the relative knowledge of the PC.