Every part of the being eventually has to open and become receptive to the higher spiritual forces. This will lead to changes in the way these aspects of the external being respond and function. This is a progressive process over time. If the lower vital parts of the being get a surge of energy from an opening, there is both a chance for this to push toward the higher implementation or for it to represent a powerful use of the energy for the normal movements of that lower vital nature. In such a case, considerable damage could be done.
The psychic being has the ability to understand and interpret the nature of the opening. If the movement is towards light, fulfillment of the higher aspiration, and an ordering of the force under the management of the spiritual dedication, then it becomes a great aid in the sadhana. If, on the other hand, all manner of lower vital energies appear, such as greed, anger, lust, craving, selfishness, then it becomes clear that the energy released is not yet transformed for the changes that need to take place.
This provides a rationale why it is best not to attempt to open and release the energies of the lower vital nature too soon, or to try to use that energy as part of the sadhana until there is considerably more control and focus by virtue of the divine force already working to transform the higher levels and aspects of the being, and these things providing a controlling and moderating influence on the lower vital forces.
Sri Aurobindo observes: “It is certainly possible to draw forces from below. It may be the hidden divine forces from below that rise at your pull, and then this motion upward completes the motion and effort of the divine force from above, helping especially to bring it into the body. Or it may be the obscure forces from below that respond to the summons and then this kind of drawing brings either tamas or disturbance — sometimes great masses of inertia or a formidable upheaval and disturbance.”
“The lower vital is a very obscure plane and it can be fully opened with advantage only when the other planes above it have been thrown wide to light and knowledge. One who concentrates on the lower vital without that higher preparation and without knowledge is likely to fall into many confusions. This does not mean that experiences of this plane may not come earlier or even at the beginning; they do come of themselves, but they must not be given too large a place.”
Sri Aurobindo, Bases of Yoga, Chapter 5, Physical Consciousness — Subconscient — Sleep and Dream — Illness, pp. 91-92
Sri Aurobindo Studies 