Buddha (c. 563-483 B.C.E.)

Like an archer an arrow,
The wise person steadies his trembling mind,
a fickle and restless weapon.
Flapping like a fish thrown on dry ground,
it trembles all day,
struggling to escape from the snares of Mara.
The mind is restless.
To control it is good.
A disciplined mind is the road to Nirvana.
(Dhammapada)