Valmiki Ramayana Sundara Kanda Sarga 49 Shloka 17
Original Shlokaअहो रूपमहो धैर्यमहो सत्त्वमहो द्युतिः। अहो राक्षसराजस्य सर्वलक्षणयुक्तता।।5.49.17।।
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राक्षसराजस्य Ravana's, रूपम् form, अहो oh, wonderful, धैर्यम् courage, अहो amazing, सत्त्वम् power, अहो is great, द्युतिः glow, अहो great, सर्वलक्षणयुक्तता endowment of all merits, अहो how great.
'Oh what charm what courage what strength what splendour How great is this demonking, an endowment of all merits.