When you abandon every desire that rises up within you,
and when you become content with things as they are, then you experience inner peace.
When your mind is untroubled by misfortune, when you desire no pleasures,
when your emotions are tranquil, and when you are free from fear and anger,
then you experience inner calm. When you are free from all attachments,
when you are indifferent to success and failure,
then you experience inner serenity.
When you can withdraw your senses from pleasures of the senses,
just as a tortoise withdraws its limbs,
then you experience inner wisdom.
~The Bhagavad Gita