The 9th century CE Dadestan i Denig (Dādestān ī Dēnīg) is a Middle Persian work by Manuščihr, who was a high priest of the Persian Zoroastrian community. This text preserves a wealth of information, primarily focusing on religious, social, ethical, and legal issues within the Zoroastrian tradition.
For a detailed study, you can refer to the full text and analysis available in sources like Iranica Online and translations available on dedicated Zoroastrian literature sites such as the Avesta.
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