"The Tibetan Book of the Dead is thought by many to be a very archaic book that describes what happens to you after you die.... That is the popular understanding of the book. The real use of the book though, the esoteric use of the book and the secret teachings, has nothing to do with that at all. The idea that death changes anything is laughed at by the enlightened teachers. This is death... Life is the bardo. The bardo is not something that you experience after death (it's that too): everything that's present after death is present now. All of the dimensions, worlds, planes of existence and, of course, nirvana, exist now, and one does not have to wait for death to experience the alternate realities or to grow towards enlightenment or be absorbed in nirvana. All of that is now, since there is no time and there is no dimension. The Tibetan Book of the Dead is not correctly named: rather, it's a Book of the Living ... or a Book of Life. It's a book that teaches you about inner states of awareness." Rama - Dr. Frederick Lenz
Talk 11 of 13 in Insights: Talks on the Nature of Existence.