I've always been fascinated by the concept of karma: what goes around comes around. Here are a few favorite quotations, and if you have more, I'd appreciate hearing them in the Comments.
"You should tremble with fear when you disrespect man, woman, chick or child. The universe has all the time in the world to grind your bitter grain, to force upon you a hateful bread..."
"My karma runs over your dogma."
"If you want to see the boomerang of karma in action, be cold, be cruel, be unjust--you can live perfectly well without half of your head, can't you?"
"I love my dogs, and my dogs love me."
Mickey Rourke, actor
"The filthy-minded man shouts out in triumph that he sees filth in a pure stream--not realizing it is his own reflection."
"The highest stupidity is for one human being to try to withhold blessings from another. Who does he think will lose in the end, who will be scoring his cheeks with his own nails and screaming with loneliness?"
"Karma is sort of like cause-and-effect, but on a diet of blood and honey."