Tirukkural-On Virtue-Avoiding Slander-Kural 182

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'To be unrighteous and do evil is bad, but to indulge in slander behind a false smile, is worse'.

Talking ill of people behind the faÇade of a sweet smile is more wicked than outright acts of unrighteousness.

The Tamil society of the Sangam age set very much store by the virtues of moral courage and straightforward behaviour. It was therefore considered the worst sin of cowardice, to talk ill of people behind their backs or under cover of beguiling smile.