Advaita Vedānta

The knowledge to be sought is knowledge of the Self as Brahman, the non-dual reality. The verse lays down the rule by which liberating knowledge is gained: it must be heard from a teacher who has directly seen the truth, because knowledge taught by one without realization, however clever with words and reasoning, does not culminate in its fruit. These commentators read the three approaches and the careful questions ('how is there bondage, how liberation, what is knowledge, what is ignorance') as the disciplined path of inquiry that wins the teacher over and makes the hearing effective. One source notes plainly that here 'knowledge is Brahman.'

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

Viśiṣṭādvaita

The 'knowledge' here is specifically the knowledge of the self that Krishna already taught earlier, from 'know that to be indestructible' down to the close of that teaching. So the verse does not introduce a new doctrine; it tells Arjuna to hear that same teaching again, now in a clear form, from those who have realized it. A real difficulty is raised and answered: was the earlier teaching not already clear? Yes, it was clear and the hearer was attentive, but because his karma-yoga is not yet complete, his inner organ is still clouded by obstructions, so the truth has not become vivid to him. As the eye sees clearly only when the right salve is applied, so when the ripening of action has dawned, in due time, the repeated hearing finally takes. The seers of truth are those with direct vision of the self's own nature, and the seeker learns 'in due time according to its ripening.'

Rāmānujācārya · Vedānta Deśika

Bhedabheda

This commentator reads the verse straightforwardly as the rule for gaining knowledge of the Self: prostration is falling down with intensity, inquiry is asking what the truth of the Self is and what knowledge and ignorance are, service is reverent attendance. He stresses, as the others do, that some who possess knowledge are still not seers of the truth, which is why Krishna qualifies the teacher; the teacher must be one who has directly realized the true reality of the Self.

Śrī Bhāskara

Dvaita

These commentators raise a sharp puzzle. If Krishna says 'know that,' does this mean Arjuna is not already a knower? Their answer: even now Arjuna is a man of knowledge, but his delusion is due to an overpowering of that knowledge, not its absence. By 'know that,' a greater knowledge is enjoined upon one who already knows. They tie this to the next verse, where Krishna speaks of 'knowing which' Arjuna will no longer be deluded: the very fact that delusion is removed by knowledge shows that what is at work is the recovery of a knower from being overpowered. The means to lift that overpowering has been stated in this verse.

Madhvācārya · Śrī Jayatīrtha

Śuddhādvaita

Here the verse is the path of grace through the guru. The threefold approach is itself the discipline of un-self-ing: bodily prostration is the practice of non-egoism, the verbal and inner approaches are reverence and affectionate inquiry toward the great. Service of the great alone is a primary means in its own right; by it the seeker becomes ripe. The teacher is to be served with the conviction that he is Bhagavan's own self-manifestation, present to bestow knowledge. The gift of jnana then comes from the realized teacher himself, not from the seeker's own effort: through the guru's lips, Bhagavan teaches. Without such a guru, knowledge of the Lord's true form does not arise; with him, it flows of itself. The threefold approach is the sign of a soul ripe for grace.

Vallabhācārya · Śrī Puruṣottama

Kashmir Shaivism

This commentator expands the means beyond the three named acts: alongside reverent salutation, devotion, inquiry and service, he includes surmise, denial, reasoning, counter-reasoning and practice, the full play of the discriminating mind. Strikingly, he reads the 'knowers' not only as outer persons but as the seeker's own faculties: for a man of knowledge like Arjuna, his own senses, favored by a particular consciousness, will bring the truth near and make him attain it; because they show the very truth, they are themselves 'seers of the truth.' He supports this with the sayings 'yoga alone is the teacher of yoga' and the Yoga-sutra line that there the insight is truth-bearing. He notes that if the verse meant only outer teachers, it could imply that what the Lord himself taught was untrue; alternatively, the verse lays down a rule that others too should take up knowledge only from the knowers, by reverent salutation and the rest, and not in any casual way.

Ācārya Abhinavagupta

Bhakti

These commentators read the verse as the constitution of the guru-disciple relationship. Each of the three limbs is a discipline of the disciple's own mind: prostration like a fallen staff breaks the pride of equal standing; inquiry ('whence is this samsara of mine, how will it cease?') demands honest acknowledgment of one's ignorance and longing; service, the long humbling of bodily attendance, burns the residue. Only into a heart so prepared can the one who has seen the truth pour what is not a mere heard report but the direct, lived experience of Brahman. One source frames the goal as the worship of the supreme Self and answers an objection that the realized may stay silent: they are not indifferent but compassionate, the very propagators of this knowledge, and so they will speak. Another, in the Marathi tradition, says service at the feet of the saints is the very threshold of the temple of knowledge, and the knowledge they impart, once it illumines the heart, stops the heart's cravings and the mind's fantasies.

Śrīdhara Svāmī · Śrīla Viśvanātha · Śrīla Baladeva · Sant Jñāneśvar

Modern

These voices read the verse as a practical, living instruction. One insists the teacher must be both Brahma-shrotri, versed in the scriptures, and Brahma-nishtha, established in Brahman; mere prostrations can be tinged with hypocrisy, so genuine faith and wholehearted service are required, and where there is real service hypocrisy becomes impossible. Another underscores that all three conditions, homage, repeated questioning and service, deserve careful attention in our age: homage means humility, service is its necessary accompaniment lest it be mock homage, and questioning is essential because without a keen spirit of inquiry there is no knowledge; all of it presupposes devotion and faith. A third reads the verse with unusual depth: Krishna here seems to send Arjuna to some other realized teacher, but his real intent is to wake Arjuna up, the way a teacher tells a disciple who lacks faith to go ask another, when in truth no other is needed; for in the thirty-eighth verse Krishna will say this very knowledge arises of itself, within oneself, while doing one's duty, once karma-yoga is accomplished. For this voice, service means shaping one's own life by the teacher's settled convictions, which the true seeker holds more dearly than the teacher holds his own body.

Swami Sivananda · Mahatma Gandhi · Lokmanya Tilak · Swami Ramsukhdas