(On Experiences) At first what has to be established comes with difficulty and is felt as if abnormal, an experience that one loses easily—afterwards it comes of itself, but does not yet stay; finally it becomes a frequent and intimate state of the being and makes itself constant and normal. On the other hand all the confusions and errors once habitual to the nature are pushed out; at first they return frequently, but afterwards they in their turn become abnormal and foreign to the nature and lose frequency and finally disappear.

Ref: Letters on Yoga Vol. III