Spectral evidence was used in court during the Salem witch trials. If someone (which they did) testified that they saw the shape of a person in their room at night in a dream, it was as good as them actually being there. The council then determined that the shape of a person was the same as a person, even though they had alibis and were miles away. Also, if one had a dream with a black cat or a wolf, that too could be used as evidence against the persons spirit proving they had connections to witchcraft based solely on an accusation. This is still the mindset we are up against.
Believing you saw something that might be a vision, might be historical, might be god, might be true, can be shared with others and accounts as hard evidence to Christians everywhere. It doesn’t matter that it can be explained neurologically, or that it can be explained naturally as a bump in a road, or that it can be debunked with updated methods or knowledge, to superstitious believers of gods that is irrelevant.