The one whose every undertaking is free of craving, and whose deeds are burned in the fire of knowledge.

Advaita Vedānta

On this reading the knowledge that burns action is the realization that the Self is actionless, the very seeing of inaction in action. Shankara distinguishes two cases. One who attains right vision before acting becomes a renouncer whose movement is only for bare survival. One who has already begun acting and then sees the Self either drops action together with its means, or, if dropping is not possible, continues acting for the world's sake without attachment, and even then does nothing whatever, since his deeds are burnt to mere inaction. Anandagiri adds that the fire of knowledge consumes only the deeds of the fit, the realized one, not of the unfit, and that scholars like the Vaisheshikas who lack realization are learned only in appearance, which is why the verse can be read as calling the true seer learned 'in reality.'

Śaṅkarācārya · Madhusūdana Sarasvatī · Śrī Nīlakaṇṭha · Dhanapati Sūri · Śrī Ānandagiri

Viśiṣṭādvaita

Here sankalpa is given a precise meaning: it is the false dwelling that identifies the self with matter and its qualities (prakriti), the mistaken attribution of guna-prompted activity to oneself. The person is freed not by denying that he acts but by dwelling instead on the self's own nature as distinct from matter, so his undertakings are free of that misidentification. His undertakings are spelled out as the obligatory, the occasional, and the desire-prompted rites, preceded by worldly acts like gathering the materials. Crucially, what the fire of knowledge burns is only the previously accumulated (prachina) store of past karma, not the action being done now and not future action; the present act actually has the form of knowledge itself. Vedantadeshika underscores that the present karma is not the long-destroyed deed but the very deed being performed, and that knowledge and its object can coexist in one act intelligibly.

Rāmānujācārya · Vedānta Deśika

Bhedabheda

This reading takes the verse at strict face value as a plain statement of fact, not as praise. Those whose undertakings are devoid of desire for fruit, whose actions are burned in the fire of the knowledge of Brahman, simply are the wise; those who act without knowing the Self simply are not. Against the view that the verse is mere eulogy, this source argues that praise only functions when it is subordinate to an injunction, as praise attached to a sacrificial command, and that is not the case here, so the verse must be read as describing the matter as it actually is.

Śrī Bhāskara

Dvaita

On this reading the state of one whose actions are burnt by the fire of knowledge is explicitly not the suppression or cancellation of action through a knowledge that deeds are unreal. That explanation is rejected as wrong. Instead, it is the knowledge that the Supreme Lord alone is the true agent: once one knows that one does not act independently of God, the very awareness of one's own non-independent agency is what it means to have one's actions burnt by the fire of knowledge.

Madhvācārya · Śrī Jayatīrtha

Śuddhādvaita

Here the freedom rests on knowledge of the Lord. Vallabha holds that by the fire of Brahman-knowledge the karma-yogi's deeds are burnt and freed from their seed-binding, so that though he acts he is verily non-acting, like a barren cow that remains a cow yet bears no calf; the doing remains, the binding is undone. Purushottama adds a devotional turn: the undertakings are done as something belonging to the Lord's command, and the one who acts this way, free of craving, is among the Lord's devotees and held in His regard; the deeds are so thoroughly burnt that even the seed-state of any future enjoyment is gone, and it is the devotees who call such a one the pandita who knows every scripturally taught form.

Vallabhācārya · Śrī Puruṣottama

Kashmir Shaivism

This source reads the verse compactly: actions done while giving up intention regarding the desires and the fruits longed for are made to enter the fire of knowledge, whose own nature has been described before and will be described further, and there they are burnt up. The emphasis falls on the act of consciously offering the deed, stripped of intention, into the fire of knowing.

Ācārya Abhinavagupta

Bhakti

These commentators carefully keep two stages distinct. Sridhara explains that for the seeker who has begun the path, once the mind has become pure, the fire of knowledge works within his actions and reduces their being-as-karma to ash; for the one already established (arudha), the attachment to fruit and the planning resolve 'for that, this is to be done' have already been given up even before action starts. Baladeva ties the burning specifically to self-knowledge that arises when purity of heart has come about, and reads the deeds as aimed at the Self. Vishvanatha presses the point furthest: even forbidden action is included here, for the qualified person sees even forbidden action as inaction, and he cites the coming verses that even the most sinful crosses over all wrongdoing by the boat of knowledge, since the fire of knowledge reduces all actions to ashes. Jnaneshwar says such a one, with the dross of the life of actions consumed in all-inclusive knowledge, is to be known as the Supreme Brahman itself.

Śrīdhara Svāmī · Śrīla Viśvanātha · Śrīla Baladeva · Sant Jñāneśvar

Modern

These voices read the verse as decisively against renouncing action and in favor of acting without desire for fruit. Tilak insists the line 'action is reduced to ashes by knowledge' does not direct the abandonment of action but the performance of action with the desire for fruit abandoned, and uses this to interpret the later phrase about 'giving up all undertakings' the same way. Sivananda says the sage acts only to set an example for the masses, doing only what bare bodily existence requires, his deeds consumed by the fire of Self-knowledge. Ramsukhdas gives a detailed psychology: repeated dwelling on sense-objects forms the conviction that they are good (sankalpa) or bad (vikalpa); when vikalpa drops and one sankalpa remains, the desire (kama) to obtain the object arises; in the one perfected by karma-yoga neither sankalpa, the cause, nor kama, the effect, remains, so his deeds, though done for loka-samgraha and to keep the chain of duty going, do not bind, and he stays untouched of himself. He stresses that the seeker should renounce both sankalpa and kama, and that the wisdom lies in the absence of motive, not the absence of action.

Lokmanya Tilak · Swami Sivananda · Swami Ramsukhdas