33 The mind is wavering and restless, difficult to guard and restrain: let the wise man straighten his mind as a maker of arrows makes his arrows straight.
34 Like a fish which is thrown on dry land, taken from his home in the waters, the mind strives and struggles to get free from the power of Death
35 The mind is frickle and flightly, it flies after fancies wharever it likes; it is difficult indeed to restrain. But it is gread good to control the mind; a mind self-controlled is a source of great joy.
36 Invisible and subtle is the mind, and it flies after fancies wherever it likes; but let the wise man guard well his mind, for a mind well guarded is a source of great joy.
From the Buddha’s teachings