Valmiki Ramayana Kishkindha Kanda Sarga 11 Shloka 22
Original Shlokaस समर्थो महाप्राज्ञस्तव युद्धविशारदः। द्वन्द्वयुद्धं महद्दातुं नमुचेरिव वासवः4.11.22।।
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महाप्राज्ञः wise, युद्धविशारदः expert in warfare, सः he, वासवः Indra, नमुचेरिव like Namuchi, तव to you, महत् great, द्वन्द्वयुद्धम् duel, दातुम् to give (challenge), समर्थः competent.
'Vali is profoundly wise, an expert in warfare. He is capable of challenging you to a duel like Indra to Namuchi.