Valmiki Ramayana Yuddha Kanda Sarga 114 Shloka 93
Original Shlokaत्यक्तधर्मव्रतंशूरंनृशंसमनृतंतथा ।।6.114.93।। नाहमर्होऽस्मिसंस्कर्तुंपरदाराभिमर्शिनम् ।
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त्यक्तधर्मव्रतम् who had given up righteous conduct, क्रूरम् cruel, नृशंसम् merciless, तथा so also, अनृतम् untrue, परदाराभिमर्शिनमसंस्कर्तुम् laid hands on others wives, अहम् I, अर्हः not deserve, न अस्मि not do
"This Ravana had given up righteous conduct, was cruel, merciless, untrue, and had laid hands on others' wives. I do not deserve to perform obsequies to him.