40. na tad anti prthivyam va
divi devesu va pun aah
sattvam prakrtijair muktam
yad ebhili syat tribhir gunaih
(40) There is no creature either on earth or again among the gods in heaven, which is free from the three modes born of nature.
gudranam ca paramtapa
(41) Of Brahmins, of KSatriyas, and Vaigyas as also of gudras, O Conqueror of the foe (Arjuna), the activities are distinguished, in accordance with the qualities born of their nature.
The fourfold order is not peculiar to Hindu society. It is of universal application. The classification depends on types of human nature. Each of the four classes has certain well-defined characteristics though they are not to be regarded as exclusive. These are not determined always by heredity.
The Gita cannot be used to support the existing social order with its rigidity and confusion. It takes up the theory of the four orders and enlarges its scope and meaning. Man's outward life must express his inward being; the surface must reflect the profundity. Each individual has his inborn nature, svabhava, and to make it effective in his life is his duty, svadharma. Each individual is a focus of the Supreme, a fragment of the Divine. His destiny is to bring out in his life this divine possibility. The one Spirit of the universe has produced the multiplicity of souls in the world, but the idea of the Divine is our essential nature, the truth of our being, our svabhãva, and not the apparatus of the guns, which is only the medium for expression. If each individual does what is appropriate to him, if he follows the law of his being, his svadharma, then God would express Himself in the free volitions of human beings. All that is essential for the world will be done without a conflict. But men rarely do what they ought to do. When they undertake to determine events believing that they know the plan of the whole, they work mischief on earth. So long as our work is done in accordance with our nature, we are righteous, and if we dedicate it to God, our work becomes a means of spiritual perfection. When the divine in the individual is completely manifested, he attains the eternal imperishable status, sasavatar madam avyayam The problem that human life sets to us is to discover our true self and live according to its truth; otherwise we would sin against our nature The emphasis on svabhava indicates that human beings are to be treated as individuals and not as types. Arjuna is told that he who fights gallantly as a warrior becomes mature for the peace of wisdom. There are four broad types of nature and answering to them are four kinds of social living. The four classes are not determined by birth or colour but by psychological characteristics which fit us for definite functions in society.
42. samo damas tapah
saucam ksantir arjavam eva ca
jnanam vi j-anam astikyam
(42) Serenity, self-control, austerity, purity, forbearance and uprightness, wisdom, knowledge and faith in religion, these are the duties of the Brahmin, born of his nature.
Those who belong to the order of Brahminhood are expected to possess mental and moral qualities. Cp. Dharnmapada, 393: "Not by matted hair, nor by lineage, nor by birth is one a Brahmin. He is a Brahmin in whom there are truth and righteousness." Power corrupts and blinds insight. Uncontrolled power is fatal to mental poise. So the Brahmins eschew direct power and exercise a general control through persuasion and love and save the wielders of power from going astray.