A book of instructions to tell you what to do when you are dead, Egyptians had a neurotic obsession with death. Around 2000 BC 8000 of these books were mass-produced by priests, who made them longer and longer for more money. Purchased at the temple, it had the owner's name typed in at the appropriate places. They were something like a medieval catholic indulgence because the book always said they were innocent and sinless.
The judgement scene is as follows: you are being led from the left side by the god, your life is in the balance, on a huge set of scales. Your heart is in a jar on the left and is weighed against the feather of truth on the right.
There were 42 questions with a deity in charge of each. If you had sinned, then your heart was heavier then the feather, then Pynuvis, the jackal god, will eat you. However, if you had not sinned you will be able to join the heavenly banquet portrayed on the top row.
Many graves have been found with these books in them. A few had epitaphs like: "Oh my heart - rise not up against me and condemn me". There was no security for the afterlife.
In the context of the Book of Exodus, this is very interesting. When it says that Pharaoh’s heart was hardened, one of the words used means to be made heavy. So when Pharaoh hardened his heart, his heart was heavy, and therefore he, the perfect god-king was condemned on the day of judgement.
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