तमुवाच हृषीकेशः प्रहसन्निव भारत।
सेनयोरुभयोर्मध्ये विषीदन्तमिदं वचः।।2.10।।
O descendant of Bharata, to him who was sorrowing between the two armies, Hrsikesa, mocking as it were, said these words:
Adi Guru starts his commentary from Gita 2.10. He explains that Gita 1.2 to 2.9 are meant to show the origin of the defect of shoka and moha which are the seeds of samsara.
The one who is inflicted by shoka and moha abdicates his swa-dharma and starts practicing para-dharma which are prohibited for him. This is like Arjun leaving his Smriti-enjoined Kshatriya-dharma of waging war and getting ready to do the prohibited karma of a mendicant.
This shoka and moha cannot be destroyed except through Atma-jnana resulting from sarva-karma-sanyas.
Objection: Liberation from shoka-moha can pretty well be accomplished by doing karma enjoined by Shruti and Smriti in conjunction with jnana. What you say that moksha is accomplished by sarva-karma-sanyas-purvak-atma-jnana is not correct.
Answer: Not so. Shruti and Smriti enjoined karmas require the presence of doership and a sense of plurality whereas jnana entails absence of doership and a sense of unity. These two obviously cannot be there simultaneously in one person. Therefore, jnana and karma cannot be practiced by same person and hence your objection is invalid.
Further, the subsequent chapters also explain this. Arjuna requests in Gita 3.1 to Bhagvan to explain the one which is better in karma and jnana. If you infer Bhagvan to enjoin the observance of both karma and jnana, then Arjuna’s question becomes meaningless. Further, Lord’s answer thereafter confirms the view that liberation is possible only by sarva-karma-sanyas.
Thus, it is clear that in Gita, at no place, has Bhagvan recommended the conjunction of Atma-jnana with karmas enjoined by either Shruti or Smriti.
The one who is involved in karmas enjoined by Shruti or Smriti due to the defects of ignorance or attachment—who later gets sattva-shuddhi, purity of heart, by yajna, dana or tapas—gets the jnana that everything is non-doer Brahman.