Valmiki Ramayana Ayodhya Kanda Sarga 12 Shloka 111
Original Shlokaप्रताम्य वा प्रज्वल वा प्रणश्य वा सहस्रशो वा स्फुटिता महीं व्रज। न ते करिष्यामि वच स्सुदारुणं ममाहितं केकयराजपांसनि।।2.12.111।।
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केकयराजपांसनि O obloquy on the house of Kekaya, प्रताम्य वा grieve, प्रज्वल वा or get burnt (in the fire), प्रणश्य वा or get destroyed, सहस्रशः into thousand pieces, स्पुटिता broken, महीम् the earth, व्रज वा reach, सुदारुणम् terrible, मम me, अहितम् harmful, ते your, वचः words, न करिष्यामि I will not do.
O obloquy on the house of Kekaya, you may grieve or burn yourself in the fire, or get destroyed. Even if you fall down on earth broken into a thousand pieces I will not act on your terrible, harmful words.