This one’s widely attributed to the Buddha, but in fact it’s a Fake Buddha Quote:
Rule your mind or it will rule you.
A quick check on Google Books revealed that it’s a translation of a line from Horace. The original quote was about controlling anger, and this is just a snippet of it, from The Routledge Dictionary of Latin Quotations:
Ira furor brevis est; animum rege, qui, nisi paret, imperat; hunc frenis, hunc tu compesce catena.
This can be translated as:
Anger is a brief madness; control your mind, for unless it obeys, it commands you; restrain it with bit and chain.
Some translations have “temper” or “passion” instead of “mind” (animus), although “mind” seems to be more literal.
The Buddha often did talk about the need to train the mind as if it were a wild animal — the metaphor Horace implies with his “bit and chain.”
In a more extended metaphor, the Buddha said that six wild animals tied together would try to go off in different directions, the overall direction of the six depending on the competing desires and relative strengths of the different beasts. This represents the mind, divided and pulled hither and thither by competing urges.
Mindfulness acts like a stake to which the six are tied:
“Just as if a person, catching six animals of different ranges, of different habitats, were to bind them with a strong rope. Catching a snake, he would bind it with a strong rope. Catching a crocodile… a bird… a dog… a hyena… a monkey, he would bind it with a strong rope. Binding them all with a strong rope, he would tether them to a strong post or stake.
“Then those six animals, of different ranges, of different habitats, would each pull toward its own range & habitat. The snake would pull, thinking, ‘I’ll go into the anthill.’ The crocodile would pull, thinking, ‘I’ll go into the water.’ The bird would pull, thinking, ‘I’ll fly up into the air.’ The dog would pull, thinking, ‘I’ll go into the village.’ The hyena would pull, thinking, ‘I’ll go into the charnel ground.’ The monkey would pull, thinking, ‘I’ll go into the forest.’ And when these six animals became internally exhausted, they would stand, sit, or lie down right there next to the post or stake. In the same way, when a monk whose mindfulness immersed in the body is developed & pursued, the eye does not pull toward pleasing forms, and unpleasing forms are not repellent. The ear does not pull toward pleasing sounds… The nose does not pull toward pleasing aromas… The tongue does not pull toward pleasing flavors… The body does not pull toward pleasing tactile sensations… The intellect does not pull toward pleasing ideas, and unpleasing ideas are not repellent. This, monks, is restraint.”
If you watch your mind for any length of time in meditation, you’ll notice that it does in fact dart here and there. Staying with the object of the meditation (e.g. the sensations of the breathing) is exceedingly difficult! Mindfulness allows us to notice when the mind has gone this way or that, and to bring it back to the breathing. Since many of the thoughts to which the mind would turn, if unrestrained, would reinforce anxiety, anger, self-doubt, etc., we find ourselves calmer and happier. A mind compassionately and mindfully restrained is a happy mind.