It is this idea that you are helpless because the vital consents to the wrong movement that comes in the way. You have to put your inner will and the Mother’s light on the vital so that it shall change, not leave it to do what it likes. If one is to be “helpless” and ruled by any part of the instrumental being, how is change possible? The Mother’s force or the psychic can act, but on condition that the assent of the being is there. If the vital is left to do what it likes, it will always go after its old habits; it has to be made to feel that it must change.
Ref : Letters on Yoga – IV