Kural - 181

Though virtuous words his lips speak not, and all his deeds are ill
If neighbour he defame not, there's good within him still

Explanation
Though one do not even speak of virtue and live in sin, it will be well if it be said of him "he does not backbite.".

Tamil Transliteration
Arangooraan Alla Seyinum Oruvan
Purangooraan Endral Inidhu.