Valmiki Ramayana Sundara Kanda Sarga 55 Shloka 15
Original Shlokaमया खलु तदेवेदं रोषदोषात्प्रदर्शितम्। प्रथितं त्रिषु लोकेषु कपित्वमनवस्थितम्।।5.55.15।।
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मया by me, रोषदोषात् due to the mistake committed angerily, त्रिषु लोकेषु in all the three worlds, प्रथितम् wellknown, अनवस्थितम् Instability, तत् that, इदम् this, कपित्वम् monkeynature, प्रदर्शितं खलु indeed exhibited.
'On account of my mistake of yielding to anger, I have exhibited the unstable monkeynature and made it well established in the three worlds.