Valmiki Ramayana Kishkindha Kanda Sarga 35 Shloka 9
Original Shlokaदेहधर्मं गतस्यास्य परिश्रान्तस्य लक्ष्मण। अवितृप्तस्य कामेषु कामं क्षन्तुमिहार्हसि।।4.35.9।।
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लक्ष्मण O Lakshmana, देहधर्मं गतस्य attending to physical needs, परिश्रान्तस्य tired person, कामेषु in lust, अवितृप्तस्य finding no satisfaction, अस्य his, कामम् love, इह now, क्षन्तुम् to pardon, अर्हसि should.
'O Lakshmana you should pardon him since he is not yet satisfied, though tired, with the struggle for the fulfilment of his sensual pleasures.