The Song now turns into a plea that the warrior who is hearing it should, as one born to be a soldier, be brave and fight, lest his sorrow for the slain be taken for fear; since “nothing is better for a warrior than a just fight,” and “loss of fame is worse than death.”  Then follows (with the usual inconsequential ‘heaven’) “If thou art slain thou wilt obtain heaven, and if thou art victorious thou shalt enjoy earth; therefore, careless of pleasure and pain, get ready for the fight, and so thou wilt not incur sin.  This is the knowledge declared in the S[=a]nkhya; hear now that of the Yoga,” and the Divine Lord proceeds: 

“Some are pleased with Vedic words and think that there is nothing else; their souls are full of desires; and they think that going to heaven is the chief thing.  Yet have the Vedas reference only to the three qualities (of which all things partake).  Be free from the three qualities (do not care for rewards).  In action, not in fruit, is the chief thing.  Do thy work, abiding by serene devotion (Yoga), rejecting every tie; be indifferent to success and failure.  Serene devotion is called indifference (to such things).  Action is lower than devotion of mind.  Devotion is happiness.  Do thou, wise in devotion, abandon the fruit that is sprung from action, and, freed from the bonds of birth, attain a perfect state.”

S[=a]nkhya here means the philosophy of religion; Yoga is the philosophical state of mind, serene indifference, religious sang-froid the practical result of a belief in the S[=a]nkhya doctrine of the indestructibility of the spirit.  In the following there is Vedantic teaching, as well as Sankhyan in the stricter sense.

On the warrior’s asking for an explanation of this state of equipoise, the Deity gives illustrations of the balanced mind that is free from all attachments, serene, emancipated from desires, self-controlled, and perfectly tranquil.  As the knight is astonished and confused at the contradiction, action and inactivity both being urged upon him, the Deity replies that there is a twofold law, that of S[=a]nkhyas consisting in knowledge-devotion, and that of Yogis in action-devotion.  Idleness is not freedom from action.  Freedom from attachment must be united with the accomplishment of such acts as should be performed.  The deluded think that they themselves perform acts, but acts are not done by the spirit (self); they are done only by nature’s qualities (this is S[=a]nkhya doctrine).  “One should know the relation between the individual and Supreme Spirit, and with tranquil mind perform good acts.  Let the deluded ones be, who are erroneously attached to action.  The wise man should not cause those of imperfect knowledge to be unsettled in their faith, but he should himself not be attached to action.  Each man should perform his own (caste) duties.  One’s own duty ill done is better than doing well another man’s work.”