Valmiki Ramayana Kishkindha Kanda Sarga 29 Shloka 26
Original Shlokaतदेवं शक्तियुक्तस्य पूर्वं प्रियकृतस्तव। रामस्यार्हसि पिङ्गेश कर्तुं सर्वात्मना प्रियम्4.29.26।।
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पिङ्गेश O king of monekys तत् that, एवं शक्तियुक्तस्य exerting all your strength, पूर्वम् earlier, तव your, प्रियकृतः done the work desired by you, रामस्य Rama's, सर्वात्मना wholeheartedly, प्रियम् dear, कर्तुम् to do, अर्हसि will be proper.
'Therefore, O king of monkeys you ought to oblige Rama wholeheartedly exerting all your strength, as he has done your work.