The second chapter is called "Sankhya Yoga". It consists of two parts: in the first Krishna tells Arjuna of the evanescent character of life as understood in Sankhya death following life and life following death endlessly; in the second part He explains in the light of Yoga how a person should act in life renouncing all attachment, undisturbed by failure or success, renouncing the fruit of action but not action itself, with senses subdued and soul controlled, and without self-conceit or selfishness.
Then Madhusudana unto him,
The Blessed Lord said:
O Arjuna, whence has come to thee
Yield not to unmanliness,
How can I, O Madhusudana,
It is better on this earth to live on alms,
What's good for us, indeed, we do not know,
My hearts overcome with taint of helplessness;
I see not anything that can remove
Thou spoke he unto Hrishikesa,
And then, O Lord of Bharata race,
The Blessed Lord said:
Thou grieves for those who need no grief,
For never was time when I was not,
As follow childhood, youth, and age
The contacts of the senses born
He who is not disturbed by these,
The unreal never can exist,
Know that is indestructible
The bodies of the embodied one,
Who thinketh him a slayer to be,
He is not born, nor ever can he die;
Who knows he's indestructible,
Just as a man his worn-out clothes discards,
Weapons can never cleave the soul,
He can never be cleft or burnt;
And he is called unchangeable,
But if thou dost believe that he
For certain is death for him that's born,
Things are unmanifest at source,
As wonderful doth someone see it all;
The dweller in each bodily frame
And looking at thy duty too,
Happy the warrior who obtains,
But if thou wilt not undertake
And then will all the people speak
"He's fled from battle out of fear,"
Many unutterable things
Slain, wilt thou attain to heaven;
Looking alike on joy and pain,
This has been taught in Sankhya form;
No effort ever comes to naught;
Their Buddhi is centered in the soul,
The foolish ones, O Pritha's son,
Full of desires, with heaven for goal,
For those who pleasure seek and power,
With Gunas three the Vedas deal;
What's in a flood of water large,
Thy duty is to act alone,
In Yoga established, do thy deeds,
Inferior far is action deemed
In Buddhi firm, doth one renounce
In Buddhi established, do the wise
And when thy Buddhi crosses over
Confounded by what thou hast heard,
What is the mark of him who's wise,
The Blessed Lord said:
When he renounces all desires,
Whose mind is not disturbed by grief,
Without attachment anywhere,
As a tortoise doth withdraws its limbs
The objects of the senses fall
The violent senses of a man,
Controlling them, the steadfast one
Thinking of objects of the sense,
From anger doth delusion rise,
But he who's free from love and hate,
And in that peace there comes to him
No Buddhi has the unsteady one,
Because the mind that follows all
Therefore, O thou of mighty arms,
When it is night for everyone,
As waters all into the ocean flow,
He who abandons all desires,
This is the state of Brahma, this
Madhusudana: A name of Krishna.
Pritha's son: Arjuna. Pritha is another name of Kunti, the mother of the Pandavas.
Hrishikesa: A name of Krishna.
Bharata race: Bharata really refers to Action. Hence it refers to all those who believe in the necessity of Action. Arjuna represents Breath or Prana, the energy of all action, and so he is called Bharata.
Sankhya: All that Krishna has so far been saying is in accordance with the teachings of the Sankhya system. This system holds that all life is subject to activity and change, and life and death and re-birth follow one another in an endless cycle of existence.
Buddhi Yoga: The Yoga system of thought, based on the character of Buddhi-Yoga has Buddhi for its foundation of thought. Krishna, having explained to Arjuna that we must act even in the light of the Sankhya system, now goes on to explain that we must do so in the light of the Yoga system too.
The foolish ones, etc: it is fools alone who believe that the Vedas teach inaction.
Gunas and Vedas: Gunas refer to Prakriti, out of which they arise. The Vedas deal with all systems of thought, including those which have Prakriti for their basis, viz., the Sankhya, Nyaya, etc.
The Vedas are very useful to a man of wisdom. They contain all knowledge of life, which may be acquired from life itself. As water In a tank Is the same as in a flood, though more handy, even so are the Vedas in relation to life.
Action is Inferior to Buddhi-Yoga: Buddhi-Yoga, or the Yoga system of thought based on Buddhi, is really concerned with action. How then can action be inferior to Buddhi-Yoga? Action here is to be understood as that which is performed with an object; for Yoga deals with action which is selfless and beneficial to all, which is performed as a Sacrifice, with renunciation of desire and fruit of action. This is made clear in the verse, where it is said that the wise ones, established in Buddhi, renounce the fruit that actions, bear, and in verse the we are told that when a person renounces all desires, he is established in Buddhi.