The Tibetan Book of the Dead is ostensibly a book describing the experiences to be expected at the moment of death, during an intermediate phase lasting forty-nine (seven times seven) days, and during rebirth into another bodily frame. This however is merely the exoteric framework which the Tibetan Buddhists used to cloak their mystical teachings. … The esoteric meaning, as it has been interpreted in this manual, is that it is death and rebirth of the ego that is described, not of the body. Lama Govinda indicates this clearly in his introduction when he writes: "It is a book for the living as well as the dying." The book's esoteric meaning is often concealed beneath many layers of symbolism. It was not intended for general reading. It was designed to be understood only by one who was to be initiated personally by a guru into the Buddhist mystical doctrines, into the pre-mortem-death-rebirth experience. These doctrines have been kept a closely guarded secret for many centuries, for fear that naive or careless application would do harm.
Timothy Leary