When a man, renouncing all thoughts, is not attached to sense objects and actions, then he is said to have attained to Yoga.
Sankara throughout his Bhagavad Gita Bhasya unmistakably teaches that most people, whose minds are not sufficiently ‘purified’ (= attenuated) for knowledge, should practise Karma Yoga (i.e. action without desire for the fruit of those actions). Once the mind has been purified, then the next step is the realisation of knowledge combined with renunciation of all action, because action cannot co-exist with knowledge. Verse 6.4 is just one example of many across BG, which repeatedly makes this point.
“The words ‘renouncing all thoughts’ imply that all desires as well as all actions should be renounced. For, all desires spring from thoughts . . . On the abandonment of all desires, the abandonment of all actions necessarily follows . . .
“Reasoning also leads to the same conclusion. For, on surrendering all thoughts, one cannot move at all. Wherefore, by saying that the aspirant should renounce all thoughts, the Lord implies that he should abandon all desires and all actions as well.”
Note that Sankara does not shy away from reasoning, explicitly recognising that the giving up of thoughts implies impossibility of movement; he clearly concurs with this conclusion.
Some wiseacres then ask how can Sankara have moved around and taught in that case? Sankara explains elsewhere in BG that there are two options for a jnani: one is that of having no property and acting only for the bare maintenance of the body (about which the Jnani is not much bothered in any event); and the other (rare exception, for he talks little of this option) is that of Janaka, acting for the sake of the world, but still without any personal desire or gain.
As set out in previous posts, desirelessness / renunciation combined with knowledge is Sankara’s final conclusion on the purport of the Upanishads, and that permeates all of his bhasya – see:
Most self-confessed Jnanis – of which there are many today on the internet – are not able to live up to this sine qua non, which betrays their actual lack of realisation. Hence the febrile convoluted protestations to argue that this was not Sankara’s intent.
Sankara was prescient about this and articulated a warning in BG 4.34:
“Some only, but not all, realise as well as know the truth. By this the Lord means to say that that knowledge alone which is imparted by those who have realised the truth, and no other knowledge, can prove effective.”
Note: Translation of Bhagavad Gita Bhasya taken from A.M.Sastry – though the sense of Gambhirananda’s and A.G.K Warrier’s translations are the same.