Action in the material world starts upon a basis of the physical body. The life energies and the mental vibrations express themselves first and foremost through physical reactions in the body. The nervous impulses travel along nerve channels and through chemical action in the form of neuro-transmitters, these impulses become sensible to the mind. Similarly when the mind wants to accomplish any action in the world, it too uses these nervous channels and chemical reactions to transmit the requisite information to the physical body to carry out that action. The body is the foundation and its limitations and weaknesses create serious obstacles for what the life-energy and the mental force can and do actually accomplish in life.
Sri Aurobindo observes: “All working of mind or spirit has its vibration in the physical consciousness, records itself there in a kind of subordinate corporeal notation and communicates itself to the material world partly at least through the physical machine. But the body of man has natural imitations in this capacity which it imposes on the play of the higher parts of his being. And, secondly, it has a subconscient consciousness of its own in which it keeps with an obstinate fidelity the past habits and past nature of the mental and vital being and which automatically opposes and obstructs any very great upward change or at least prevents it from becoming a radical transformation of the whole nature.”
This describes the nature of the difficulties that the seeker is asked to deal with: “It is evident that if we are to have a free divine or spiritual and supramental action conducted by the force and fulfilling the character of a diviner energy, some fairly complete transformation must be effected in this outward character of the bodily nature.”
The answer is not to take the more traditional route of denigrating or avoiding the body and its needs. “The body is given to us as one instrument necessary to the totality of our works and it is to be used, not neglected, hurt, suppressed or abolished. if it is imperfect, recalcitrant, obstinate, so are also the other members, the vital being, heart and mind and reason. It has like them to be changed and perfected and to undergo a transformation. As we must get ourselves a new life, new heart, new mind, so we have in a certain sense to build for ourselves a new body.”
Sri Aurobindo, The Synthesis of Yoga, Part Four: The Yoga of Self-Perfection, Chapter 14, The Power of the Instruments, pp. 701-702