This is the bare source of Purusha, the witness.
Yoga Sutra Vibhuti Pada:
tad vairagyad api dosha bija kshaye kaivalyam ||50||
तद्वैराग्यादपि दोषबीजक्षये कैवल्यम् ॥५०॥
tad-vairāgyād-api doṣa-bīja-kṣaye kaivalyam ||50||
Non-attachment (vairagya) even from that omiscience destroys the foundation of all dysbalances (dosha) and results in liberation (kaivalya). ||50||
tad = (acc. sg. n. /nom. sg. n.) that
vairāgyat = (ab. sg. n. from vairāgya) desirelessness; non-attachment; dispassion
api = (conj./prep.) even
doṣa = (iic.) impurity; dysbalances
bīja = (iic.) seed; foundation
kṣaye = (loc. sg. m./acc. du. n./nom. du. n./loc. sg. n. /acc.du. f./nom. du. f . from kṣaya) destruction
kaivalyam = (acc. sg. n./nom. sg. n. from kaivalya) liberation; enlightenment
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