But even if a person isn't religious, if they have had no delusions otherwise even a "religious experience" isn't necessarily seen as a warning sign, as long as it isn't accompanied by other more troubling hallucinations (visual, auditory, etc.). But if that person has a history of delusions, hallucinations, etc. that can change circumstances.

So really it varies on a case by case basis. Each patient gets looked at individually, their past experiences and belief systems and what they're experiencing, and of course it is slightly affected by the personal bias of the psychologist (even though they are supposed to remain as objective as possible, you can't avoid some biases). A good psychologist will never shown their bias though, and their personal feelings about religion will not show through in the diagnosis and treatment of a patient.

I also have to disagree with the above statement that most psychologists and psychiatrists are "at odds" with religion. I have met many psychologists, some of whom were religious and some were not. But the ones who weren't religious weren't at odds with religion, and didn't look down on it. Maybe some do, but to say that a majority of people in the field are atheists would be a gross overestimation IMO.