Thirukkural-On Avoiding Vulgarity-Kural-455

Thirukkural 455, Avoiding Vulgarity
Mananthuymai seyvinaith thooymai irandum
Inanthuymai thoovaa varum

Purity of mind and purity of actions
Spring from purity of associations.

Therefore, in order to understand man"s mind and the quality of his actions, it is necessary to identify and assess the quality of his friends and associates.

A very strong statement in the negatively worded as follows occurs in Kambaramayanam:
“Theeyavar saerthal seythaar thooyavar allar" (Kambaramayanam: Sadaayu, 54)