Valmiki Ramayana Yuddha Kanda Sarga 64 Shloka 18
Original Shlokaयस्यनास्तिमनुष्येषुसदृशोराक्षसोत्तम । कथमाशंससेयोद्धुंतुल्येनेन्द्रविवस्वतोः ।।6.64.18।।
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राक्षसोत्तम best of Rakshasas, यस्य his, सदृशः great, मनुष्येषु of all the human beings, नास्ति not, इन्द्रविवस्वतोः Indra and Sun god, तुल्येन equal, योद्धुम् in war, कथम् how, आशंससे enter into combat.
"O Best of Rakshasas! How would you enter into combat with one who is great among all human beings and while even Indra and Sun God are not equal to him in war?"