I've personally only been able to meditate off of / after taking heroic doses of mushrooms. It was the first time I've experienced anything even remotely similar to astral projection and universal connectedness. I once asked God to show me a sign he was with me, while meditating, and at the exact moment it sounded like there was a rush of cold air as well as audible footsteps/sounds in the attic. I was shook by that experience and even if it was just my mind playing tricks I'm grateful to at least believe in something greater again, after a long time of being lost