I shall read a few verses of the 4th chapter.14&15 give the nature of the divine Work.
na māṁ karmāṇi limpanti na me karma-phale spṛhā |
iti māṁ yo ’bhijānāti karmabhir na sa badhyate ||14|| (IV)
evaṁ jñātvā kṛtaṁ karma pūrvair api mumukṣubhiḥ |
kuru karmaiva tasmāt tvaṁ pūrvaiḥ pūrvataraṁ kṛtam ||15|| (IV)
“Actions do not bind Me, nor do I have yearning for the fruit of actions. He who knows Me thus is not bound by actions.”
“Knowing thus the seekers of liberation performed deeds in ancient times. In the same way, you also perform actions as done in the past by your forefathers.”
Basic point is that you do actions, and yet, you do not get bound by actions: this is the nature of the divine Consciousness. If you attain to this Consciousness then you become the divine worker.
From verse n°16, there is the analysis of the real meaning of Karma. This is as it were a reiteration, a kind of a summing up of the whole of the Karmayoga, in which what is demonstrated is that mere action by itself is not Karmayoga; although even by actions, mere actions, you can produce many results, because every action has a result.
The Karma is karma only when you know akarma behind it: the real action is action only when you know that there is non-action behind it. Action proceeding from non-action and action getting burned into non-action: that is the true knowledge of action. The Immobile giving rise to Mobility and Mobility getting silenced into the Immobility, when this state is reached, that is Karmayoga, and that is the real knowledge of Karma. As long as you see only action by itself, you are still bound by action.
Sri Krishna says:
kiṁ karma kim akarmeti kavayo ’py atra mohitāḥ |
tat te karma pravakṣyāmi yaj jñātvā mokṣyase ’śubhāt ||16|| (IV)
“What is karma and what is akarma? In this regard, kavayo ’py , even the sages, atra mohitāḥ, they are bewildered; tat te karma pravakṣyāmi, it is that action that I will explain to you; yaj jñātvā, knowing which; mokṣyase ’śubhāt, you will come out of evil.”
karmaṇo hy api boddhavyaṁ boddhavyaṁ ca vikarmaṇaḥ |
akarmaṇaś ca boddhavyaṁ gahanā karmaṇo gatiḥ ||17|| (IV)
“You should know what is Karma; you should also know what is Vikarma; what is Akarma that also you should know, profound and secret is the movement of Karma.”
Now, is the most famous sentence of the Bhagavad Gita:
karmaṇy akarma yaḥ paśyed akarmaṇi ca karma yaḥ
sa buddhimān manuṣyeṣu sa yuktaḥ kṛtsna-karma-kṛt ||18|| (IV)
“One who sees action in inaction, and one who sees inaction in action, it is he among the intelligent ones, he is a Yogi. kṛtsnakarmakṛt, and yet who is capable of doing all activity.”
kṛtsna-karma-kṛt: karma is action, kṛtsna means entirety. For him it is not as if he can do this action, and not that action. Among the ritualists there is a prescription: you should do only these actions, and not those actions, but a yogi is one who can do all actions, because the Divine is present everywhere, the Divine is doing all actions in the world, He is omnipresent; and he is like the Divine Himself, he is a divine worker; so, nothing is untouchable for him. Only, he should know that inaction is action, and in inaction there is action; when he knows this secret, when immobility is known as mobility, and in mobility when you see immobility, when you see this, then you become the divine worker.