Shri Krishna praised both the renunciation of works and work with devotion. Arjun is confused by these apparently equivocal instructions and wishes to understand which of the two is more auspicious for him.
The first chapter described the nature of Arjun’s grief and created the setting for Shri Krishna to begin to relate spiritual knowledge to him.
In the second chapter, Shri Krishna revealed to Arjun the science of the self and explained that since the soul is immortal, nobody would die in the war, and hence it was foolish to lament. He then reminded Arjun that his karma (social duty) as a warrior was to fight the war on the side of righteousness. But, since karma binds one to the fruits of actions, Shri Krishna encouraged Arjun to dedicate the fruits of his works to God. His actions would then become karma-yoga, or “united with God through works.”
In the third chapter, Krishna explained that performing one’s duties is necessary because it helps to purify the mind.
In the fourth chapter, Shri Krishna explained the various kinds of sacrifices (works that can be done for the pleasure of God). He concluded by saying that sacrifice performed in knowledge is better than mechanical ritualistic sacrifice. He also said that all sacrifice ends in the knowledge of one’s relationship with God.