The religious experience which we are studying is that which lives itself out within the private breast. First-hand individual experience of this kind has always appeared as a heretical sort of innovation to those who witnessed its birth. Naked comes it into the world and lonely; and it has always, for a time at least, driven him who had it into the wilderness …

William James (1842-1910) American psychologist and philosopher
The Varieties of Religious Experience, Lectures 14-15 “The Value of Saintliness” (1902)
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