ii:38 – having made pleasure and pain, gain and loss, victory and defeat the same – by so doing, you will never incur sin.
Here is a clever argument based on the highest wisdom! In karma yoga, the action itself is the goal, and its performance its sufficient reward. Hence, whatever happens in consequence is joyously welcomed. Duty-consciousness at once lifts one’s mind above the pairs of opposites given here by Krsna.
Pain and pleasure, etc., are mental modifications brought about by the contact or identification of the soul (purusa) and the world (prakrti) – (XIII:20).
But here, what we need bear in mind is the central fact that we are prevented from doing our duty in this world by perverted notions of pain and pleasure, gain and loss, and so on. Instinctively we avoid pain and we refuse to do that which (we fear) might cause pain or loss to us, even if that is our sacred duty. Our own intellect now comes to the aid of this behaviour, and we weave very clever arguments to justify our action and make it appear righteous. This is precisely where man with his intelligence can be worse than beast which is totally instinctual in its behaviour.
Equanimity and a balanced mind which regards pain and pleasure alike are the indispensable prerequisites to the performance of one’s own dharma and, hence, to the attainment of salvation.