Advaita Vedanta · attributed to Shankaracharya
Nirvana Shatakam, stanza 2
Not breath, not the sheaths, not the organs of action
न च प्राणसंज्ञो न वै पञ्चवायुर्न वा सप्तधातुर्न वा पञ्चकोशः। न वाक्पाणिपादौ न चोपस्थपायू चिदानन्दरूपः शिवोऽहं शिवोऽहम्॥
I am not vital breath, nor the five vital winds. Not the seven constituents of the body, not the five sheaths. Not speech, not hands, not feet. I am Consciousness-Bliss. I am Shiva. I am Shiva.
What this verse points to
The second stanza moves to the subtler layers — the vital breaths, the bodily constituents, the five sheaths — territory that a practitioner might well have started to identify with after some experience of pranayama.
That is the point of its placement. The subtle body is the most tempting thing to mistake for the Self, precisely because reaching it takes effort.
Sit with it
After breathwork, notice any sense of having become subtler, and set that down too.
About the Nirvana Shatakam
Also called Atma Shatakam — six stanzas, each stripping away another layer of what one takes oneself to be (mind, breath, emotion, virtue, relationship, form) and each closing with the same refrain: chidananda rupah shivoham, "I am consciousness and bliss; I am Shiva." It is a negation practice in the form of a hymn.
References to this text are given as stanza — here, 2.