One's own duty, even poorly done, even stripped of its qualities when carried out, is more excellent, more to be praised, than another's duty well carried out, even though accomplished with all its qualities. For one established in his own duty even death is better than the life of one established in another's duty. Why? Because another's duty brings fear: it brings the fear marked as hell and the rest. Although it has been said that the root of all ill is the brooding on objects (Gītā 2.62), and that passion and aversion are this man's waylayers, that was said scattered and not settled. Wishing to know it gathered and settled as just this one thing, so that, once it is known, he might make an effort to root it out, Arjuna said.

Therefore the discipline of action, which is one's own duty and is easy to do, though it lack a quality, yet carrying freedom from heedlessness within it, is better than the discipline of knowledge, which is another's duty for one joined with matter, since it is hard to do, though it have a quality, even when carried out for a little while, and since it is liable to heedlessness. For one who abides in the discipline of action, which is his own duty because it is fit for him to take up by himself, even death, with the fruit unattained in a single birth, is better; for, the way being unbroken by harm, there is the possibility, in the very next birth, of beginning the discipline of action unagitated. For one joined with matter, the discipline of knowledge, being another's duty since it cannot be taken up by himself, is, by carrying heedlessness within it, fraught with fear.

This is a brief sub-gloss. For a fuller reading of this verse, see Madhusūdana, Śaṅkara, or Rāmānuja above.

Even so, the action of war is a fierce one, one might think; so Krishna says with 'better is one's own dharma'.