Fluctuations in Aspiration and Sadhana

These fluctuations in the force of the aspiration and the power of the sadhana are unavoidable and common to all sadhaks until the whole being has been made ready for the transformation. When the psychic is in front or active and the mind and vital consent, then there is the intensity. When the psychic is less prominent and the lower vital has its ordinary movements or the mind its ignorant action, then the opposing forces can come in unless the sadhak is very vigilant. Inertia comes usually from the ordinary physical consciousness, especially when the vital is not actively supporting the sadhana. These things can only be cured by a persistent bringing down of the higher spiritual consciousness into all the parts of the being.

Ref : Letters on Yoga Vol. III