The sequence survives in Seleucid-era ritual texts. Days one to three: prayers and purifications at Esagila. Day four: the high priest reads Enuma Elish to Marduk's statue; Nabu arrives from Borsippa. Day five: the king surrenders the royal insignia, the priest strikes his cheek, pulls his ear, and forces him to kneel for the negative confession: I have not sinned, Lord of the lands; I have not destroyed Babylon; I have not made Esagil quake; I have not struck the cheek of the privileged citizens. The insignia are returned, a second slap tests for tears, and tears mean Marduk is pleased. Days eight to eleven: the gods decree destinies, process to the bit akiti outside the walls, and return. Nabonidus recorded bringing 6,021 minas of silver and 307 of gold to the festival house.
The twentieth century's grand reading, Frazer, the myth-ritual school, Eliade: the humiliation reenacts the cosmic drama, the king dies symbolically with the old year and rises with the new, and the whole festival is the universe's annual reboot, chaos defeated, order restored. Textbooks repeated it for decades as what the Akitu meant.
Jonathan Z. Smith's deflation: the surviving texts are Seleucid, and the confession's crimes, scattering Babylon's people, neglecting its temple, humiliating its citizens, are things only a foreign conqueror could be accused of. The ritual, he argues, is a rectification of a foreign king, nationalistic religious propaganda from a city under occupation, not timeless cosmic drama. On this reading the slap is Babylon's annual reminder to its latest foreign ruler of who owns the gods.
What kind of state builds an annual ceremony where the ruler must publicly swear he has not destroyed his own capital?