And Sri Krishna answers:
kāma eṣa krodha eṣa rajo–guṇa–samudbhavaḥ |
mahāśano mahā–pāpmā viddhy enam iha vairiṇam ||37|| (III)
What is it that throws you into sinful action even when you don’t want it?
The answer is: kāma, krodha, only two things. Basically kāma, because krodha comes from kāma. We have been told already in the second chapter kāma jayate krodhaḥ, from kāma arises anger; kāma eṣa krodha, basically it is kāma. It is the desire which is rajo–guṇa–samudbhavaḥ, which arises out of rajoguṇa, out of Rajas, arises kāma, from where arises krodha; it is because of this: mahāśano mahā–pāpmā viddhy enam iha vairiṇam, realise that it is that which is the destroyer, it is that which is the maker of your sinful action, know him to be your vairiṇa: your desire is your enemy.
This kāma, is expounded; what is the nature of kāma:
dhūmenāvriyate vahnir yathādarśo malena ca |
yatholbenāvṛto garbhas tathā tenedam āvṛtam ||38|| (III)
“Just as the fire gets clouded by smoke, just as a mirror is spoiled by the dust, just as the embryo is covered by olbenā, by placenta, tenedam āvṛtam, similarly this one, your true Self gets covered up by kāma.”
āvṛtaṁ jñānam etena jñānino nitya–vairiṇā |
kāma–rūpeṇa kaunteya duṣpūreṇānalena ca ||39|| (III)
This is the nitya–vairi, that which is the enemy, this kāma, āvṛtaṁ jñānam, because of this kāma, even jñānam becomes āvṛtaṁ. Even when you have knowledge, it becomes covered up: even when you are a Jnani, jñānino jñānam. Even if you are wise, even if you have wisdom, even that gets completely covered up by this vairi, by this enemy: kāma–rūpeṇa kaunteya duṣpūreṇānalena ca ||
It is like a fire, which can never be satisfied duṣpūreṇā: it is a fire, which wants more and more and more. Desire, once you satisfy it…a further desire; you satisfy it…further desire. It is like putting fuel into the fire: it is by this kāma, that even wisdom gets covered up.
indriyāṇi mano buddhir asyādhiṣṭhānam ucyate |
etair vimohayaty eṣa jñānam āvṛtya dehinam ||40|| (III)
How does this kāma works? By what means in our composition of psychology it works? The senses, mind and intellect are set to be in dwelling places: this desire has a dwelling place in our senses, in our mind, in our intellect. Enveloping wisdom by these, it deludes embodied souls. These are three things: the senses, the mind, and the intellect.
tasmāt tvam indriyāṇy ādau niyamya bharatarṣabha | (III, 41)
Therefore, control indriyā and others: your senses, your mind and intellect. They need to be controlled; pāpmānaṁ prajahi: slay this sinful thing; hy enaṁ jñāna–vijñāna–nāśanam: it is this kāma, which destroy jñāna–vijñānanā. Even if you possess jñāna–vijñāna, knowledge and the full knowledge, all that is destroyed by this kāma; therefore, pāpmānaṁ prajahi: prajahi is an order: slay it.