"This is really the book I didn't want to write...It wasn't until 1974 that I discovered that this teaching had been neglected completely, and then finally lost, in the western world."
(from the author's introduction to The American Book of the Dead, by E.J. Gold)
The readings from The American Book of the Dead for the being are the direct teachings of the guides - you may think of them as teachers, sufis, arhats or bodhisattvas - and the instructions have been rendered into modern American English.
Just as a midwife assists birth, the reader of The American Book of the Dead assists voyagers who have passed into the macrodimensions to attain liberation or to achieve a conscious and deliberate rebirth -- commonly called, from the organic view, a lifetime. (from How To Use This Book excerpted from The Professional Labyrinth Reader's Handbook)
It isn't necessary to understand the readings. Shortly before transition as well as passing through, the being has an all-embracing clarity of vision and understanding. The reading will reach the part of the person that's actually passing into the macrodimensional domains and in that state understanding comes naturally.