Kural - 864

His wrath still blazes, every secret told; each day
This man's in every place to every foe an easy prey

Explanation
He who neither refrains from anger nor keeps his secrets will at all times and in all places be easily conquered by all.

Tamil Transliteration
Neengaan Vekuli Niraiyilan Egngnaandrum
Yaanganum Yaarkkum Elidhu.