Let the yogin, the meditator, ever, at all times, yoke, gather, the self, the inner instrument, dwelling in solitude, in a lonely place, a mountain cave and the like, alone, without a companion. From the qualifications 'dwelling in solitude' and 'alone', it follows that he has made renunciation. He whose mind and self, the mind being the inner instrument and the self the body, are both restrained; free of longing, free of craving; without possessions, free of belongings: even though a renouncer, having relinquished all possessions, let him so yoke himself. Now, for one who practises yoga, the rule of seat, food, conduct and the rest, as the means of yoga, must be told, and the marks of one who has attained yoga, and its fruit; so the topic is begun. First the seat itself is told.

The yogin, settled in the discipline of action of the manner described, should constantly, day by day, at the time of discipline, yoke the self; that is, he should make the self joined, make it settled in the beholding of itself. Standing in a solitary place, void of people and without sound, alone, not even there with a companion, there too with mind and self restrained, free of longing, with no expectation toward the whole of the thing other than the self, without possession, free of the sense of mine toward anything whatever other than that.

This is a brief sub-gloss. For a fuller reading of this verse, see Madhusūdana, Śaṅkara, or Rāmānuja above.

Krishna states the manner of the yoga of samadhi, with 'let him join himself to yoga' and the rest. 'Let him join' means let him make himself joined to the yoga of samadhi. 'The self' here means the mind.