It is clear to Sri Krishna that Arjuna will not be swayed by philosophical considerations alone, and he therefore next turns his attention to the role and highest ideals of the warrior caste, the kshatriya, to which Arjuna belongs. The principles enunciated here speak to the entire background, training and education that Arjuna has received and if anything, they speak to a deeply-ingrained sense of nobility and chivalry that was the highest ideal of the warrior.
Arjuna should not let the sorrow of the loss of friends, family and loved-ones intervene in the high ideals that he has adopted. Sri Aurobindo explains Sri Krishna’s argument: ” ‘There is no greater good for the Kshatriya than righteous battle, and when such a battle comes to them of itself like the open gate of heaven, happy are the Kshatriyas then. If thou dost not this battle for the right, then has thou abandoned thy duty and virtue and they glory, and sin shall be they portion.’ ”
Arjuna’s despair sets forth the sin of undertaking the action. Sri Krishna counters with the sin of failure to act when the cause is just and the situation demands it. “Battle, courage, power, rule, the honour of the brave, the heaven of those who fall nobly, this is the warrior’s ideal. To lower that ideal, to allow a smirch to fall on that honour, to give the example of a hero among heroes whose action lays itself open to the reproach of cowardice and weakness and thus to lower the moral standard of mankind, is to be false to himself and to the demand of the world on its leaders and kings.”
For Arjuna is fixated on his own individual suffering, but he is the representative man of his age, and his actions provide guidance and direction to others. He has a duty to fulfill and a role to play and abandoning that would lead to confusion and a retrograde motion in society.
Sri Aurobindo, Essays on the Gita, First Series, Chapter 7, The Creed of the Aryan Fighter, pg. 60,
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