2.3.15
यदा सर्वे प्रभिद्यन्ते हृदयस्येह ग्रन्थयः। अथ मर्त्योऽमृतो भवति एतावदनुशासनम् ॥१५॥
yadā sarve prabhidyante hṛdayasyeha granthayaḥ। atha martyo'mṛto bhavati etāvadanuśāsanam ॥15॥
[यदा (yadā) - when; सर्वे (sarve) - all; प्रभिद्यन्ते (prabhidyante) - are broken; हृदयस्य (hṛdayasya) - of the heart; इह (iha) - here; ग्रन्थयः (granthayaḥ) - knots; अथ (atha) - then; मर्त्यः (martyaḥ) - mortal; अमृतः (amṛtaḥ) - immortal; भवति (bhavati) - becomes; एतावत् (etāvat) - this much; अनुशासनम् (anuśāsanam) - instruction;]
When all the knots of the heart are broken, the mortal becomes immortal; this is the essence of the teaching.
Bhāṣya 2.3.15
'Knots of the heart' are nothing but the knots of false knowledge.
मिथ्याज्ञानग्रन्थिभिस्तु नितरां मुच्यते यदा। तदाऽमृतत्वमेवैति तदर्थं चानुशासनम् ॥१५॥
mithyājñānagranthibhistu nitarāṃ mucyate yadā। tadāmṛtatvamevaiti tadarthaṃ cānuśāsanam ॥15॥
[मिथ्या (mithyā) - false; ज्ञान (jñāna) - knowledge; ग्रन्थिभिः (granthibhiḥ) - knots; तु (tu) - but; नितरां (nitarāṃ) - completely; मुच्यते (mucyate) - is released; यदा (yadā) - when; तदा (tadā) - then; अमृतत्वम् (amṛtatvam) - immortality; एव (eva) - indeed; एति (eti) - attains; तदर्थं (tadarthaṃ) - for that purpose; च (ca) - and; अनुशासनम् (anuśāsanam) - instruction;]
When one is completely released from the knots of false knowledge, then indeed one attains immortality; for that purpose is the instruction.