Your Worst Enemy-- is with your mind unguarded
"Your worst enemy cannot harm you as much as your own mind, unguarded.
But once you mastered, no one can help you as much,
not even your father, mother, or any other relatives"
"Wheresoever fear arises, it arises in the fool, and not in the wise man."
"Hatred is never appeased by hatred in this world. It is appeased by love.
This is an eternal law."
"He who is observant of others' faults, and is always irritable,
increases his own defilements. He is far from the destruction of defilements"
"Mind is forerunner of all good and bad mental states.
If one speaks or acts with pure mind,
because of that, happiness follows one,
even as one's shadow that never leaves."
All the above Quotes are from Buddha's teaching and some buddhist text.