The body is the servant of the mind. It obeys the operations of the mind, whether they be deliberately chosen or automatically expressed. At the bidding of the unlawful thoughts the body sinks rapidly into disease and decay; at the command of glad and beautiful thoughts it becomes clothed with youthfulness and beauty.
…
Thoughts of malice, envy, disappointment, despondency, rob the body of its health and grace. A sour face does not come by chance; it is made by sour thoughts.
…
Thoughts of doubt and fear never accomplish anything, and never can. They always lead to failure. Purpose, energy, power to do, and all strong thoughts cease when doubt and fear creep in.
– James Allen (As a Man Thinketh)
I like those snippets, Joe. It blurs poetry and prose, and reminded me so much of this:
I must not fear.
Fear is the mind-killer.
Fear is the little-death that brings total obliteration.
I will face my fear.
I will permit it to pass over me and through me.
And when it has gone past I will turn the inner eye to see its path.
Where the fear has gone there will be nothing.
Only I will remain.
Frank Herbert, from the Dune series of novels.
http://en.wikipedia.org/wiki/Litany_against_fear