The concept of Dharma is often considered to be one that is universal, eternal and unchanging. This idea incorporates the sense that we can identify an idealized form of dharma that can be used, at all times, as a “pole star” to guide our actions. Sri Aurobindo reminds us that in the ideal sense, this is true; but in the world of manifestation, the concept of Dharma necessarily must evolve and grow as our capabilities to understand and embody Dharma grow. The process of the growth of Dharma in the manifested world over time involves concurrently the recognition that there are powers and movements within the world that resist, oppose and try to prevent or at least slow down the development of dharma.
Various religions have recognized this process of progressive and retrogressive movements. The Vedic seers spoke of the powers of darkness covering up and opposing the light. Buddha had to face down the temptations of Mara in order to achieve his enlightenment. The Zoroastrian religion posited two opposing principles, that of Light and that of Darkness that ever strived to overcome one another. Christianity sets up a similar opposition of God and Satan. Clearly the understanding of the dynamic between powers that are attempting to bring greater illumination to our lives and those that oppose the changes that come about when new powers of knowledge or action arise, is one that has been recognized throughout the world over a great span of time.
The development of Dharma is a progressive process, as Sri Aurobindo explains “…because man does not already possess the ideal or live in it, but aspires more or less perfectly towards it, is growing towards its knowledge and practice. And in this growth Dharma is all that helps us to grow into the divine purity, largeness, light, freedom, power, strength, joy, love, good, unity, beauty, and against it stands its shadow and denial, all that resists its growth and has not undergone its law, all that has not yielded up and does not will to yield up its secret of divine values, but presents a front of perversion and contradiction, of impurity, narrowness, bondage, darkness, weakness, vileness, discord and suffering and division, and the hideous and the crude, all that man has to leave behind in his progress. This is the adharma, not-Dharma, which strives with and seeks to overcome the Dharma, to draw backward and downward, the reactionary force which makes for evil, ignorance and darkness.”
The role of the Avatar involves aiding the development of Dharma and overcoming the power of the reactionary forces of resistance.
Sri Aurobindo, Essays on the Gita, First Series, Chapter 17, The Divine Birth and Divine Works, pg. 163