Calmness, self-control, austerity, cleanliness, clemency, honesty, knowledge, wisdom and faith in the Supreme – these are the natural activities of a brahmana.
Bhagavad Gita - Chapter 18 - Moksha Yoga - The Yoga of Supreme Perfection
Heroism, power, steadfastness, dexterity, never fleeing from battle, generosity and social administration – these are the natural activities of a kshatriya.
Farming, cow protection and business are the natural activities of a vaishya. For the shudra there is service to others.
Now please hear from Me how those who perform their prescribed duties attain all perfection.
Human beings achieve perfection through prescribed duties by worshipping the Supreme Person, from whom all things originate and who is omnipresent.
It is better to perform one’s own duty (dharma) imperfectly than to perform another’s duty perfectly. One is never subject to bad karma by performing one’s prescribed duties according to one’s own nature.
O son of Kunti, one’s prescribed duties must never be abandoned. All activities are covered with some fault, just as smoke covers fire.
The stage of perfect renunciation is attained by becoming unattached to material objects, disregarding material enjoyments, by doing ones duty and being unattached to the results.
O son of Kunti, now learn from Me how one can attain perfection by acting in the way that I shall now briefly describe to you.
With pure intelligence, controlling the mind with determination, abandoning attachment to sense-objects, being devoid of both attachment and hatred, residing in a secluded place, eating little, controlling speech, body and mind, being constantly engaged in meditating on the Supreme Person, being renounced, free from egotism, the misuse of power, conceit, lust, anger, covetousness and being unselfish and peaceful – such a person is qualified for realization of the Absolute Truth.