To say that one had “seen the light” is a poor description of the mental rapture which only the convert knows…. The new light seems to poor in from all directions across the skull; the whole universe falls into pattern like the stray pieces of a jigsaw puzzle assembled by magic at one stroke. There is now an answer to everyone question, doubts and conflicts are a matter of the tortured past…. Nothing henceforth can disturb the convert’s inner peace and serenity — except the occasional fear of losing faith again, and losing thereby what alone makes life worth living. And falling back into the outer darkness.

Arthur Koestler describing the conversion experience to Communism, but possibly broadly applicable to many conversion experience and ideation large and small.