Videvdad (Vendidad)

The Law Against the Demons, the sole complete surviving book of the twenty-one-volume Sasanian Avestan canon, organized into 22 chapters called fargards. It opens with a myth of sixteen perfect lands created by Ahura Mazda, each countered by a plague from the hostile Angra Mainyu, then recounts the legendary king Yima and the underground shelter he built to survive a mythic winter. Later fargards are dominated by purity law: detailed rules on handling corpses and dead matter, menstrual seclusion, hair and nail disposal, and the nine-night Barashnum purification rite, alongside chapters on contracts and the origins of medicine. It was composed orally in Younger Avestan over the same broad period as the rest of the Younger Avesta, roughly 1000-400 BC, with its written form fixed only under the Sasanians centuries later; the dating here reflects compositional history, not manuscript date. Its exact location within that eastern Iranian world is unknown.