Krishna, seeing all these kinsmen arrayed here to fight, my mind reels; I can hardly stand, for my limbs grow limp. My mouth is as parched dry as desert sand; my body quivers. The mighty Gandiva bow slips from my fingers wet with sweat; my skin is on fire. What greater crime is there than killing one's own friends and relatives? What gain is victory, what use sovereignty, what joy in wealth and pleasures, what value life itself, if gained by killing one's loved ones? It is a great sin, Krishna. I cannot do it. How can we ever live happily hereafter, if we kill our own people? I cannot do it, Krishna. I prefer to be poor, and live as a beggar, or a pauper. Krishna, I cannot fight.
He casts away his bow and arrows and sinks down in his chariot in utter dejection.
And who cannot sympathise with him? After all the tribulations of the years and decades leading up to this date; after all the negotiations ofr peace and preparations for war, Arjuna is finally face to face with what the war will actually mean. On the enemy side are men beloved to him: his teacher, Drona; his uncle, Salya. Most of all, the dear Grandsire of the entire clan, Bhishma. The Kauravas themselves are first cousins of the Pandavas. The enormity of what he is about to do stands before him stark and horrifying, and to refuse to fight at first glance seems the noble response.
But Krishna will have none of it:
You grieve in vain, Arjuna; the wise grieve neither for the dead nor for the living. For there is no time that I did not exist, nor you, nor any of these warriors: and there is no time we shall not exist hereafter. The body dies, but not the living spirit within it. Know this, and do your duty; without grief.
The embodied soul attains the stages of childhood, youth, maturity and old age: leaving the body, it goes on to another. The body is born only to perish again: but That which pervades body and soul cannot die or be killed.
Bodies slay and are slain on the vast tapestry of Time and Space: but the eternal Self is imperishable, immeasurable; an immutable principle, indestructible. It is not born, it does not die. It is constantly eternal: the same yesterday, today and for evermore; pure unchanging consciousness. Weapons cannot kill that Self, fire cannot burn it, water cannot wet it, wind cannot dry it. It is eternal, all-pervading, stable, immovable, primordial.
With these words Krishna summarises the entire Gita, and gets to the very core of Hinduism: we are not the body. The body goes through many changes: it is born, grows, moves through the stages of childhood, adolescence, adulthood and old age; and then it dies. There is no constancy in the body, no permanence. What is permanent is the sense of being which every one of us experiences: the child, the adult, the old woman. That knowledge of "I Am" is like a silved thread that accompanies us all through our lives. Though our minds may change, our attitudes, our likes and dislikes, our hobbies, indeed, even our sex, there is SOMETHING there beyond all these, a constant sense of one's own existence: that is the life within us upon which all these changes move and flicker like the pictures on a screen.
That, says Krishna, cannot be killed. It is not the agent throughout all the changes; it is merely the observer, the silent witness, the true Self of all. It occupies the body, it occupies the mind, but it is neither of these. It is the mystery beyond all the appearances that distract us day and night. It is the true reality.
That is the teaching of Hinduism, of the Vedas and Upanishads and the Bhagavad Gita in a nutshell.