At the time I thought it was a phase. My mother was always talking (tongue-in-cheek?) about her "parking angel" and burning incense, so I thought he had just picked up that part of her personality.
Turns out he had (and still has, many years later) schizophrenia so he was genuinely using his considerable intelligence to try and make sense of what he saw, heard and felt, drawing on any "truth" he could find.
It really put me off religion and spirituality for a very long time. If these concepts weren't out there and accepted by so many people, maybe he would have been diagnosed and treated sooner and be in a better place today. I don't know.
These days I do think some amount of religion/spirituality is positive, and I think in total it makes the world a better place, but if I ever felt that kind of epiphany personally I know I would head straight to the nearest mental hospital.