In his lectures on Raja Yoga, Swami Vivekananda points out clearly that chasing after powers or siddhis as they are called, is not the aim of the yoga and can be a distraction from the primary goal. They may come, but should not be sought after or made a primary determinant of the yogic process nor set as a goal of any sort. Similarly, Sri Aurobindo has emphasized that the eventual supramental transformation, while it will clearly have impacts on the physical body does not have as its goal the conquest of death or the seeking for immortality of the body. In fact, he goes on to state that such a step would be at the tail end of a long process, not something immediate that the seeker could or might expect as a result of the yogic practice. In order to achieve this, not only the mind has to be illumined and the vital force enhanced, but the very cells of the body would need to become conscious, responsive and capable of adaptation far beyond where they are in today’s world.
Sri Aurobindo writes: “Death is there because the being in the body is not yet developed enough to go on growing in the same body without the need of change and the body itself is not sufficiently conscious. If the mind and vital and the body itself were more conscious and plastic, death would not be necessary.”
“As for conquest of death, it is only one of the sequelae of supramentalisation — and I am not aware that I have forsworn my views about the supramental descent. But I never said or thought that the supramental descent would automatically make everybody immortal. The supramental can only make the best conditions for anybody who can open up to it then or thereafter attaining to the supramental consciousness and its consequences. But it could not dispense with the necessity of sadhana. If it did, the logical consequence would be that the whole earth, men, dogs and worms would suddenly wake up to find themselves supramental. There would be no need of an Ashram or of yoga.”
“Why vital? What is vital is the supramental change of consciousness — conquest of death is something minor and, as I have always said, the last physical result of it, not the first result of all or the most important — a thing to be added to complete the whole, not the one thing needed and essential. To put it first is to reverse all spiritual values — it would mean that the seeker was actuated, not by any high spiritual aim but by a vital clinging to life or a selfish and timid seeking for the security of the body — such a spirit could not bring the supramental change.”
Sri Aurobindo, Integral Yoga: Sri Aurobindo’s Teaching and Method of Practice, Chapter 8, The Triple Transformation: Psychic, Spiritual and Supramental, The Supramental Transformation, pp. 229-237