Rushing mind.

The mind is restless, unsteady,
hard to guard, hard to control.
The wise one makes it straight,
like a fletcher straightens an arrow.

How good it is to rein the mind
which is unruly, capricious, rushing wherever it pleases
The mind so harnessed will bring one happiness.

Your worst enemy cannot harm you
as much as your own unguarded thoughts.
a well-directed mind creates more happiness.
Than even the loving actions of your parents.

Buddha Shakyamuni, quoted by Joseph Goldstein.