Weighing of souls
During the contest of Achilles and Hector in the Iliad, Zeus, weary from the battle, hung up his golden scales and in them set twin Keres, "two fateful portions of death"; this, then, is known as the kerostasia. Plutarch reports that Aeschylus wrote a play with the title Psychostasia, in which the combatants were Achilles and Memnon. This tradition was maintained among the vase painters. An early representation is found on a black-figure lekythos in the British Museum; she observes "The Keres or φυχαί are represented as miniature men; it is the lives rather than the fates that are weighed. So the notion shifts." In a psychostasia on an Athenian red-figure vase of about 460 BCE at the Louvre, the fates of Achilles and Memnon are in the balance held by Hermes.  Among later Greek writers the psychostasia was the prerogative of Minos, judge of the newly deceased in Hades.
In Egyptian mythology, where Duat is the Underworld, there would take place the Weighing of the Heart, in which the dead were judged by Anubis, using a feather, representing Ma'at, the goddess of truth and justice responsible for maintaining order in the universe. The heart was the seat of the life-spirit (ka). Hearts heavier or lighter than the feather of Ma'at were rejected and eaten by Ammit, the Devourer of Souls.
For Christians, among the terrors that await at the Last Judgment is the weighing of souls. Sin is heavy, and sinful souls are to be consigned forever to Hell. The courtly angelic knight in the central panel of Hans Memling's The Last Judgment, ca 1470 (National Museum Gdańsk), is the Archangel Michael, who separates the Just from the Damned in his steelyard balance. Memling has treated a medieval genre of fresco, called in English examples a "Doom" which kept the future terrors before the eyes of the faithful.
- Iliad, XXII.208-213.
- J.V. Morrison, "Kerostasia, the Dictates of Fate, and the Will of Zeus in the Iliad" Arethusa 30.2, Spring 1997, pp. 276-296.
- Harrison 1922, p. 183; Harrison reports that in the Onomasticon of Pollux, Zeus and his attendants were suspended above the action in a crane.
- BM B639, line drawing is Harrison's fig. 26, p.184
- Musée du Louvre G399, Beazley Archive.
- Matthew Bunson, Angels A to Z (New York:Crown), 1996.