Valmiki Ramayana Yuddha Kanda Sarga 49 Shloka 13
Original Shlokaत्वंनित्यंसुविषण्णंमामाश्वासयसिलक्ष्मण । गतासुर्नाद्यशक्तोऽसिमामार्तमभिभाषितुम् ।।6.49.13।।
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लक्ष्मण Lakshmana, त्वम् you were, नित्यम् always, सुविषण्णम् sad, माम् me, आश्वासयसि comforted, अद्य now, गतासुः ceased of life, आर्तम् grieved, माम् me, अभिभाषितुम् to comfort, शक्तः capable, नासि not.
"You were always comforting me when I was sad. Now however much I am grieved, ceased of life you cannot comfort me."