Thus, in this way, by the Lord the wheel of the world, founded on Veda and sacrifice, has been set turning. He who, here in the world, eligible for action, does not keep it turning lives a sinful life, his very life sin; he takes his sport, his play, in the senses, in objects, and so is one whose delight is in the senses. In vain, O Pārtha, does he live. So the meaning of the topic is that the ignorant person eligible for action must do action. The performance of the yoga of action, undertaken for the sake of the knowledge of the Self, is to be done by the eligible person who does not know the Self, until he gains the fitness for steadfastness in the knowledge of the Self; this is set out from 'not by the non-undertaking of actions' (Gītā 3.4) down to 'the maintenance of your body too would not be accomplished by inaction' (Gītā 3.8), and from 'apart from action for the sake of sacrifice' (Gītā 3.9) down to 'in vain, O Pārtha, does he live' (Gītā 3.16) many reasons were incidentally given for the performance of action by the eligible person who does not know the Self, and the fault in not doing it was set out. This being so, the question may arise, or rather, anticipating Arjuna's question, whether this wheel, thus set turning, is to be kept turning by everyone, or whether the steadfastness in the yoga of knowledge, which is to be carried out by the Sāṅkhyas, the knowers of the Self, is to be reached by the one who does not know the Self only through the means of the yoga of action stated above, and not by one who has not yet reached it. To make plain the meaning that this scripture of the Gītā wishes to set out, the meaning of the scripture 'having known this very Self, the brāhmaṇas, their false knowledge stilled, rising up from the desires for sons and the rest that the falsely-knowing must necessarily pursue, wander forth to a life of mere begging undertaken only for the maintenance of the body, having no task left them apart from steadfastness in the knowledge of the Self', the Blessed Lord says the following.

This wheel, set turning thus by the supreme Person, in 'from food beings come to be', the word 'beings' denoting living bodies; from rain, food; from sacrifice, rain; and sacrifice from action that conforms to the doer's working; and action from the living body; and the living body again from food; turning like a wheel by this mutual relation of effect and cause, whoever, qualified for the discipline of action or the discipline of knowledge, while standing in the means, does not follow it on, does not set it turning, not keeping up the body with what is left over from sacrifice, he is one whose life is sin. His life is for the beginning of sin, or ripens into sin, or is both; so he is one whose life is sin. And for that very reason he delights in the senses, not in the self: the senses become his pleasure-gardens; with body and mind fattened by what is not left over from sacrifice, his rajas and tamas grown strong, turned away from the beholding of the self, he has his single delight in the enjoyment of objects. So, though he strive at the discipline of knowledge and the rest, his effort being utterly fruitless, in vain, Partha, does he live. The Lord says that the non-undertaking of the action suited to caste and stage of life, the great sacrifices and the rest, belongs only to the liberated man, whose beholding of the self does not depend on a means.

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

And those letters are made manifest by beings; such is the wheel. He who does not keep this wheel of the world turning, since he is its destroyer, is one whose life is sin (aghayu), as the gloss runs, 'he whose life is given over to sin alone is an aghayu'.