My initial visionary experiences were absolutely mind blowing for me, although when I told my rationalist friends about them they took them as evidence of a delusionary frame of mind. It was like trying to describe television to someone from a pre-technological culture. What really seemed to confuse my friends was that I was doing cutting edge geological research in seismo-tectonics at the same time. They took Science and mysticism to be mutually contradictory, whereas I found them to be mutually enriching. Because mysticism is rooted in direct experience, no faith is involved.
Religious faith is based on accepting the infallibility of the mystical experiences of dead people.
The problem here is that the most profound parts mystical experiences can not be communicated in words. This inherent ambiguosity has lead to some serious argument and bloodshed. Think of how many Christians have died over the nature of the Trinity. One does not see warring groups of scientists killing each other over the precise value of the speed of light. The Abrahamic religions are deeply hostile to mysticism largely because mystical experiences have the power to upset the status quo.