‘In some ancient initiatic traditions, candidates had to face one final trial. They would be placed in a sarcophagus, and there they stayed for three days and three nights, watched over by their Masters. By means of secret methods known only to them, their Masters kept them in a hypnotic trance and, detaching their astral and etheric bodies from their physical body, allowed them to travel through space and visit every region of creation.
They saw hell and heaven; they were amazed, bewildered, terrified and ecstatic in turn; they touched truth itself. And when their etheric and astral bodies were reunited with their physical body, the bonds that bound them to each other were of a totally different nature. Everything the disciples had seen, all the impressions and experiences they had lived through, were now recorded in their brain, and they could remember it all in detail.’
Omraam Mikhaël Aïvanhov
Izvor Book 209, Christmas and Easter in the Initiatic Tradition