Tirukkural-On Virtue-Avoiding Slander-Kural 194

Add as a preferred source on Google

He who speaks vain and graceless words in public assembly
Will expose his want of essential goodness and moral rectitude.

It might appear that Valluvar is labouring a relatively minor matter, far too much. On the contrary, the practice of indulging in loose and purposeless talk in decent congregations, has limitless potential for causing harm to himself and to others and so Valluvar"s emphasis is certainly not overdone.

Christ"s teaching too has a parallel import on this issue:

'But I say unto you, that every idle word that men shall speak, they shall give account thereof on the day of judgment'.
(Matt, 12:23)