Valmiki Ramayana Kishkindha Kanda Sarga 58 Shloka 14
Original Shlokaरामस्य यदिदं कार्यं कर्तव्यं प्रथमं मया। जरया च हृतं तेजः प्राणाश्च शिथिला मम।।4.58.14।।
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रामस्य Rama's, यत् if, इदं कार्यम् this task, मया by me, प्रथमम् first, कर्तव्यम् duty, हृतम् should be done, प्राणाश्च vitality, शिथिलाः reduced, मम my, जरया due to old age, तेज: strength.
'Rama's work is my primary duty. (But) my strength is drained by age and I have lost my vitality.