The Spiritual Transformation

The power of concentration above the head is to bring peace, silence, liberation from the body sense, the identification with mind and life and open the way for the lower (mental-vitalphysical) consciousness to rise up to meet the higher Consciousness above and for the powers of the higher (spiritual or divine) Consciousness to descend into mind, life and body. This is what is called in this Yoga the spiritual transformation.

Ref: Letters on Yoga – III