Duat

The Duat is the ancient Egyptian underworld, but it is better understood as a nocturnal passage than a static place. Every night the sun god Ra descends into it, sailing his barque through its twelve regions, one for each hour of the night, to be regenerated and rise again at dawn; and the dead must make the same perilous journey to reach the paradise of Aaru.

The Duat is a realm of gates and guardians, demons and lakes of fire, its geography mapped in extraordinary detail by the funerary texts painted on tomb walls and coffins, the Book of the Dead, the Amduat ("that which is in the Duat"), the Book of Gates, which functioned as guidebooks for the deceased, supplying the spells, passwords, and names needed to pass each obstacle safely. Its culminating trial is the weighing of the heart in the Hall of the Two Truths, where the heart is balanced against the feather of Maat before Osiris and forty-two assessor gods; the unworthy heart is devoured by the monster Ammit, ending the person's existence entirely, while the justified pass on. The Duat expresses a profound Egyptian idea: that death, like the nightly darkness, is a passage to be navigated with knowledge, and that rebirth, of the sun and of the soul, is won each time through trial.

The Duat is the best documented afterlife in the ancient world because the Egyptians drew it on the walls. The Amduat, the Book of Gates and the Book of Caverns are compositions painted in New Kingdom royal tombs, and they are structured as an itinerary: twelve hours of the night, each with its own gate, its own guardians, its own inhabitants, and text naming them. Knowing the names is the point, because a gate opens for someone who can address its keeper correctly.

What the sun does there is the organising event. Ra enters the west, travels the twelve hours, unites with Osiris at the deepest point, and is reborn in the east at dawn. The dead king travels with him. Every sunrise is therefore a demonstration that the passage works, which is a considerably stronger argument for an afterlife than assertion.

The texts also record a social change. The Pyramid Texts of the Old Kingdom were for the king. The Coffin Texts of the Middle Kingdom appear on the coffins of officials. The Book of the Dead of the New Kingdom could be bought as a papyrus, sometimes with blanks left for the purchaser's name. Over roughly a thousand years the passage through the Duat went from a royal prerogative to something available to anyone who could pay a scribe.