The third chapter of the Bhagavad Gita is Karma Yoga or the Path of Selfless Service. Here Lord Krishna emphasizes the importance of karma in life. He reveals that it is important for every human being to engage in some sort of activity in this material world. Further, he describes the kinds of actions that lead to bondage and the kinds that lead to liberation. Those persons who continue to perform their respective duties externally for the pleasure of the Supreme, without attachment to its rewards get liberation at the end.
Those men who ever follow this teaching of Mine with faith and without cavil, they also become freed from actions.OPEN VERSE
But those who, decaying [Finding fault where there is none.] this, do not follow My teaching, know them-who are deluded about all knowledge [Knowledge concerning the qualified and the un-qualified Brahman.] and who are devoid of discrimination-to have gone to ruin.OPEN VERSE
Even a man of wisdom behaves according to his own nature. Beings follow (their) nature. What can restraint do?OPEN VERSE
Attraction and repulsion are ordained with regard to the objects of all the organs. One should not come under the sway of these two, because they are his adversaries.OPEN VERSE
One's own duty [Customary or scripturally ordained observances of different castes and sects.], though defective, is superior to another's duty well-performed. Death is better while engaged in one's own duty; another's duty is fraught with fear.OPEN VERSE