Kural - 422

Wisdom restrains, nor suffers mind to wander where it would;
From every evil calls it back, and guides in way of good

Explanation
Not to permit the mind to go where it lists, to keep it from evil, and to employ it in good, this is wisdom.

Tamil Transliteration
Sendra Itaththaal Selavitaa Theedhoreei
Nandrinpaal Uyppa Tharivu.