Valmiki Ramayana Sundara Kanda Sarga 37 Shloka 51
Original Shlokaअथ रक्षांसि भीमानि महान्ति बलवन्ति च। कथञ्चित्सांपराये त्वां जयेयुः कपिसत्तम।।5.37.51।।
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कपिसत्तम O noble monkey, अथ then, भीमानि fearsome, महान्ति massive, बलवन्ति च powerful, रक्षांसि demons, सांपराये in the fight, कथञ्चित् in any case, त्वाम् you, जयेयुः win over.
"O noble monkey the massive, fearsome and powerful demons may defeat you in the fight in any way.