Valmiki Ramayana Bala Kanda Sarga 31 Shloka 10
Original Shlokaधनुषस्तस्य वीर्यं तु जिज्ञासन्तो महीक्षित:। न शेकुरारोपयितुं राजपुत्रा महाबला:।।1.31.10।।
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राजपुत्रा: princes, महाबला: possesing mighty strength, महीक्षित: kings, तस्य धनुष: that bow's, वीर्यम् prowess, जिज्ञासन्त: intent on knowing, आरोपयितुम् attempted to lift or string it, न शेकु: failed.
Mighty princes and kings have failed to string it, in their attempt to know its strength.