“Pathologic” generally means “related to or indicitave of a disease process”. It’s best to think of it as the opposite of “physiologic”, which refers to normal body function.
When it comes to mental illness, pathology is a lot like pornography–hard to define, but you know it if you see it. If someone thinks Regis Philbin is talking directly to him from the television and telling him to kill his dog, most of us would think of that as pathologic. If he hears Regis talking to him late at night when the TV isn’t on, that’s still fairly clear-cut.
However, if the same person hears God talk to him late at night, we don’t think of that as especially abnormal–depending on what he says. If he says that God is telling him to kill his dog, we’re back to inarguable pathology.
This is because our societal norms include belief in a God who converses with us one-on-one, and who would not tell any of us to kill his dog. It’s an interesting little No True Scotsman-type arrangement–we’ll believe it’s actually God talking to you if he says something that sounds like something we believe God would say. Anything else, and it wasn’t really God.
Probably for certain pathologies and not for others. The resident that I’m working with right now says that since the Left Behind books came out, she’s seen all sorts of people having anxiety attacks because they’re so concerned about being “left behind”. I think it’s because most of these folks came from the same Eastern KY Unexamined Religion tradition I did, and while they always heard about Jesus coming back someday, they never really considered the details.