Valis by Philip K. Dick
The first of Dick's three final novels (the others are Divine Invasion and The Transmigration of Timothy Archer). Known as science fiction only for lack of a better category, "Valis" takes place in our world and may even be semi-autobiographical.
The proponent of the novel, Horselover Fat, is thrust into a theological quest when he receives communion in a burst of pink laser light. From the cancer ward of a bay area hospital to the ranch of a fraudulent charismatic religious figure who turns out to have a direct com link with God, Dick leads us down the twisted paths of Gnostic belief, mixed with his own bizarre and compelling philosophy. Truly an eye opening look at the nature of consciousness and divinity.
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