I don't really make a distinction between "religious experiences" and "non-religious experiences". My life is a series of experiences, all of them interconnected, and the line that might divide "religious experiences" from "non-religious experiences" has become increasingly obscured.
Perhaps the first spontaneous mystical experience that I remember which I've written about a few times here on the forum might be along the lines of what you're looking for...
I used to work on weekends and during the summer with my step-father, who was a plastering contractor in Chicago. We lived about 60 or so miles northwest of the city in a little town called Woodstock, so the commute took around an hour and a half with the morning stop at the material yard.
One morning, I was staring out the window of the truck at the buildings, the traffic, the people, the El (the elevated/subway train system that runs through the city) when out of nowhere I felt a sense of familiarity and intimacy with all of it...everything...as familiar as my living room or the back of my hand...like it was a part of me. I don't recall, even at the time, how long this lasted...probably just a few seconds...but the gravity of the experience made an impression on me that I would never forget, even though for years I wrote it off as some sort of an anomaly.
It wasn't until many years passed that I was talking to someone about the experience, and they suggested that it might be what they referred to as a spontaneous mystical experience. It was at that time which began to investigate, research, talk, contemplate, and meditate on the experience. I learned more about it, and it was able to find validation in Hindu scripture that verified with me that it was not just an anomaly. It pointed to what I am in my true nature.
The writers of the Bible knew anything about God? I’ve heard from several people who feel they know God. They will say with certainty what God is like. The problem of course is that what they claim is not consistent with each other. I understand people feeling they have personnel knowledge...
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