Valmiki Ramayana Bala Kanda Sarga 55 Shloka 19
Original Shlokaप्राप्य चास्त्राणि राजर्षिर्विश्वामित्रो महाबल:। दर्पेण महता युक्तो दर्पपूर्णोऽभवत्तदा।।1.55.19।।
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महाबल: endowed with supreme power, राजर्षि: rajarshi, महता by great, दर्पेण pride, युक्त: endowed with, विश्वामित्र: Visvamitra, तदा then, अस्त्राणि weapons, प्राप्य having obtained, दर्पपूर्ण: अभवत् filled with insolence.
Rajarshi Viswamitra endowed with supreme power became very haughty. Having obtained the weapons, his insolence was greatly accentuated.