Thirukkural- On Virtue - Penance-Kural-264

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Destruction of the foes to penance and the blessing of friends,Will instantly arise from the strength of penance.

While discussing the power of penance, Parimelalagar would say that real ascetics are above foes and friends, and will not stoop to differential treatment of either; and that is why the poet has chosen to refer to the foes and friends of penance itself, and not of the sage. The quality of the penance will itself ensure the destruction of foes and blessings from friends.

Kambaramayanam endorses the idea when it says,Izaitha theevinaiyaiyum kadakka yennudhal
Thazaitha paeraruludaith thavathinaagu mael

(Kambar-Mandiram 25)