Habbits of Physical and Vital Nature

The habits of the physical or the vital-physical nature are always the most difficult to change, because their action is automatic and not governed by the mental will and it is therefore difficult for the mental will to control or transform them. You have to persevere and form the habit of control. If you can succeed in controlling the speech often,—it needs a constant vigilance,—you will finally find that the control extends itself and can in the long run always intervene. This must be done so long as that movement is not fully opened to the Mother’s Light and Force, for if that happens the thing can be done more quickly and sometimes with a great rapidity. There is also the intervention of the psychic—if the psychic being is sufficiently awake and active to intervene each time you are going to speak at random and say “No”, then the change becomes more easy.

Ref : Letters on Yoga Vol.IV