Kural - 653

Who tell themselves that nobler things shall yet be won
All deeds that dim the light of glory must they shun

Explanation
Those who say, "we will become (better)" should avoid the performance of acts that would destroy (their fame).

Tamil Transliteration
Oodhal Ventum Olimaazhkum Seyvinai
Aaadhum Ennu Mavar.