Given the mind’s propensity to treat a mental acceptance as an actual accomplishment in the world, it is not only possible, but likely, that the seeker will adopt the “idea” of the abandonment of the fruit of works while the outer actions and reactions continue. Various justifications and excuses come before the mind to “distinguish” these reactions from any desire for the fruits of the work on some level. And thus, the transformation of the consciousness gets subtly blocked at the mental level and cannot work itself out throughout all the planes and parts of the being.
In order to provide the seeker with a way to work through this web of illusion on the mental plane, much of it suggested by the clever suggestions of the vital nature, the Gita sets up a clear “test” for how one can determine that the abandonment of the fruits of the work is true, complete and unwavering.
Sri Aurobindo discusses this issue: “The test it lays down is an absolute equality of the mind and the heart to all results, to all reactions, to all happenings. If good fortune and ill fortune, if respect and insult, if reputation and obloquy, if victory and defeat, if pleasant event and sorrowful event leave us not only unshaken but untouched, free in the emotions, free in the nervous reactions, free in the mental view, not responding with the least disturbance or vibration in any spot of the nature, then we have the absolute liberation to which the Gita points us, but not otherwise. The tiniest reaction is a proof that the discipline is imperfect and that some part of us accepts ignorance and bondage as its law and clings still to the old nature. Our self-conquest is only partially accomplished; it is still imperfect or unreal in some stretch or part or smallest spot of the ground of our nature. And that little pebble of imperfection may throw down the whole achievement of the Yoga!”
Sri Aurobindo goes on to point out that there are intermediate steps or “approximations” of equality that should not be confused with the state of consciousness that the Gita is describing. It is not a status that derives from disappointed expectation of desire, or pride or indifference, all of which are forms of ego driven by the modes of Nature, the three Gunas. “There is too, on a higher level, the equality of the stoic, the equality of a devout resignation or a sage detachment, the equality of a soul aloof from the world and indifferent to its doings. These too are insufficient; first approaches they can be, but they are at most early soul-phases only or imperfect mental preparations for our entry into the true and absolute self-existent wide equal oneness of the spirit.”
Sri Aurobindo, The Synthesis of Yoga, Part One: The Yoga of Divine Works, Chapter 3, Self-Surrender in Works–The Way of the Gita, pp. 95-96