Thirukkural

கற்க கசடறக் கற்பவை கற்றபின் நிற்க அதற்குத் தக.

Karka kasadara karpavai katrapin nirka adharkuth thaga.

Learn thoroughly whatever you learn, free of flaw - and having learnt, live in a manner worthy of that learning. (Thirukkural 391.)