With body, mind, intellect, and even the senses alone, yogis perform action, giving up attachment, for the purification of the self.
Explanation
Krishna continues describing how a person can act without being bound. Yogis act through body, mind, intellect and senses, but without attachment (saṅga), and their aim is inner purification (ātma-śuddhi), not personal gain. Traditions differ on the word "kevalaiḥ" ("only/alone"): some take it as acting with the senses free of any sense of "I am the doer", others as acting without craving for results.