Vīdēvdād is the only complete Nask of the
Sassanian Avesta, the sacred book of the Zoroastrian religion,
that has been transmitted to us in its complete Sassanian
version. According to the Dēnkard the books of the Avesta were
divided in three categories: gathic, ritual and legal.
The legal text are divided since the Avestan in the law of Zaraθuštra
and the law of Vīdēvdād (dāta- vīdaēuua-). The latter
handled mainly on prescriptions against nasu- "corpse"
and the demoness concerning witth it (druj- nasu-).
Therefore, the Nask Vīdēvdād consisted in
originally only of prescriptions in order to remove impurity
from the pure elements of the creation of Ahura Mazdā. However,
through many centuries of transmission, another texts about
different matters have been incorporated to it, such as the
mythical creation of the sixteen lands and their
countercreations (V 1), Yima’s mythical kingship and his
protection of the whole creation (V 2), the goddess of the earth
(V 3), contracts and punishment for breaking them (V 4), proper
dog’s care (V 13), sin for killing an otter and its atonement (V
14) , Θrita and the origin of the medicine (V 20) and the origin
of the diseases (V 22). On the other side only V 5-12, V 16-17,
partly V 18-19 and V 20 deal with different themes related to
impurity and its purification and the removing of the evil
forces. Thus the Sassanian text of Vīdēvdād which has arrived to
our time sums 22 chapters (phl. fragard), but not all of
them seem to have belonged in origin to the Vīdēvdād Nask.