The literature of religious experience abounds in references to the pains and terrors overwhelming those who have come, too suddenly, face to face with some manifestation of the Mysterium tremendum, In theological language, this fear is due to the incompatibility between man’s egotism and the divine purity, between man’s self-aggravated separateness and the infinity of God. Following Boehme and William Law, we may say that, by unregenerate souls, the divine Light at its full blaze can be apprehended only as a burning, purgatorial fire. An almost identical doctrine is to be found in The Tibetan Book of the Dead, where the departed soul is described as shrinking in agony from the Clear Light of the Void, and even from the lesser, tempered Lights, in order to rush headlong into the comforting darkness of selfhood as a reborn human being, or even as a beast, an unhappy ghost, a denizen of hell. Anything rather than the burning brightness of unmitigated Reality — anything!

— The Doors of Perception and Heaven and Hell by Aldous Huxley (Page 46 - 47)