Mind is the wielder of muscles. The force of a hammer blow depends on the energy applied; the power expressed by a man’s bodily instrument depends on his aggressive will and courage. The body is literally manufactured and sustained by mind. Through pressure of instincts from past lives, strengths or weaknesses percolate gradually into human consciousness. They express as habits, which in turn ossify into a desirable or an undesirable body. Outward frailty has mental origin; in a vicious circle, the habit-bound body thwarts the mind. If the master allows himself to be commanded by a servant, the latter becomes autocratic; the mind is similarly enslaved by submitting to bodily dictation.
— The Tiger Swami - Autobiography Of A Yogi