From Chapter Four ("The Pebble") of The Miracle of Mindfulness by Thich Nhat Hanh (translated by Mobi Ho):
The mind is like a monkey swinging from branch to branch through a forest, says the Sutra. In order not to lose sight of the monkey by some sudden movement, we must watch the monkey constantly and even to be one with it. The Sutra says to be one with it. Mind contemplating mind is like an object and its shadow—the object cannot shake the shadow off. The two are one. Wherever the mind goes, it still lies in the harness of the mind. The Sutra sometimes uses the expression "Bind the monkey" to refer to taking hold of the mind. But the monkey image is only a means of expression. Once the mind is directly and continually aware of itself, it is no longer like a monkey. There are not two minds, one which swings from branch to branch and another which follows after to bind it with a piece of rope.
^z - 2009-11-21