The Gita consistently takes up concepts that were current in its day and integrates them into an inclusive standpoint. The integrating principle is based on the inner spiritual life and knowledge, not the outer form. The same approach can be seen in the way the Gita addresses the four orders of life, which was turned into a fixed outer social and economic order over time in India. The Gita is not attempting to support or justify this outer system, but rather, trying to express an inner truth that guides the seeker to the Swabhava, the true inner being that the individual is born to express and fulfill, and from there to the Swadharma, the “work to be done” according to the inner law of one’s being.
Sri Aurobindo takes up this point: “And from this emphasis on the inner truth and not on the outer form arises the spiritual significance and power which the Gita assigns to the following of the Swadharma.”
As to the caste system, “In fact it lays very little stress on the external rule and a very great stress on the internal law which the Varna system attempted to put into regulated outward practice. And it is on the individual and spiritual value of this law and not on its communal and economic or other social and cultural importance that the eye of the thought is fixed in this passage.”
As with other principles, “…here too and in the same way it accepts the theory of the four orders of men, but gives to it a profound turn, an inner, subjective and universal meaning, a spiritual sense and direction. And immediately the idea behind the theory changes its values and becomes an enduring and living truth not bound up with the transience of a particular social form and order. What the Gita is concerned with is not the validity of the Aryan social order now abolished or in a state of deliquescence,–if that were all, its principle of the Swabhava and Swadharma would have no permanent truth or value,–but the relation of a man’s outward life to his inward being, the evolution of his action from his soul and inner law of nature.”
Sri Aurobindo, Essays on the Gita, Second Series, Part II, Chapter 20, Swabhava and Swadharma, pg. 497