The Upanishad is one of the older, "primary" (
mukhya)
Upanishads. It is contained within the
Shatapatha Brahmana, and its status as an independent Upanishad may be considered a secondary extraction of a portion of the Brahmana text. This makes it one of the old (if not the oldest) texts of the Upanishad corpus, dating to roughly the
8th to
7th centuries BCE. It is associated with the
Shukla Yajurveda. It figures as number 10 in the
Muktika canon of 108 Upanishads and was notably commented upon by
Adi Shankara.
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