Valmiki Ramayana Ayodhya Kanda Sarga 37 Shloka 3
Original Shlokaयो हि दत्त्वा द्विपश्रेष्ठं कक्ष्यायां कुरुते मनः। रज्जुस्नेहेन किं तस्य त्यजतः कुञ्जरोत्तमम्।।2.37.3।।
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यः such a man, द्विपश्रेष्ठम् best of elephants, दत्त्वा having given away, कक्ष्यायाम् rope tied to its girth, मनः mind, कुरुते will do, कुञ्जरोत्तमम् best elephant, त्यजतः of a man while giving up, तस्य his, रज्जुस्नेहेन for attachment for the rope, किम् why?
Having given away the best of elephants, will any one be interested in the rope tied to its girth? Why should one have any attachment for the rope after he has given up the elephant?