Thirukkural- On Virtue- Hypocrisy-Kural-274

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One who indulges in vice under cover of a saint's trappings, Is like a bird-catcher lying in wait behind a bush.

There have always been some people, who have used the cover of their high position to commit low crime – expecting that their 'holy habit will cleanse their foul soul'. They are the people who are compared here to the third-rate hunter lying in wait behind a bush to catch birds. It is such people Periapuranam castigates as those who commit crime and vice under cover of ascetic roles and looks.
Thavam maraindhalla seythaar