Valmiki Ramayana Bala Kanda Sarga 59 Shloka 17
Original Shlokaये दूषयन्त्यदुष्टं मां तप उग्रं समास्थितम्। भस्मीभूता दुरात्मानो भविष्यन्ति न संशय:।।1.59.17।।
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उग्रम् rigorous, तप: penance, आस्थितम् adopted, अदुष्टम् free from blemish, माम् me, ये who, दूषयन्ति abused, दुरात्मान: wickedminded ones, भस्मीभूता: reduced to ashes, भविष्यन्ति will become, संशय: न no doubt.
"I am blameless. I have practised rigorous penance. These wicked ones who have abused (a sage like me) will be reduced to ashes.