Bhagavad Gita · Jnana Karma Sannyasa YogaChapter 4, Shloka 16 (4.16)

A question that seems simple — a deep answer. "Action" and "inaction" — everyone thinks this is obvious: moving about is action, sitting still is inaction. Krishna says — even the learned are confused about it.

Shankaracharya: na caitat tvayā mantavyam — karma nāma deha-ādi-ceṣṭā loka-prasiddham, akarma nāma tad-akriyā tūṣṇīm āsanam — kiṃ tatra boddhavyam — do not think that action means bodily movement (as is commonly known), and inaction means stopping it, sitting still — what is there to understand in that? The answer (4.17): there is something deep in this.

Acharya Ramanuja — action and the knowledge within it. Mumukṣuṇā anuṣṭheyaṃ karma kiṃ-svarūpam, akarma ca kim — what kind of action should a seeker of liberation perform, and what is "inaction"? According to Ramanuja, karma = phalābhisandhi-rahitaṃ bhagavad-ārādhana-rūpaṃ karma — action free from desire for results, in the form of worship of the Lord; akarma = kartuḥ ātmano yāthātmya-jñānam — knowledge of the true nature of the self who acts. Even the learned do not know the true nature of these two. Evam antargata-jñānaṃ yat karma tat te pravakṣyāmi — such action, with knowledge within it, I shall explain to you.