Valmiki Ramayana Yuddha Kanda Sarga 22 Shloka 34
Original Shlokaतस्यतद्वचनंश्रुत्वासागरस्यराघवः । मुमोचतंशरंदीप्तंवीरस्सागरदर्शनात् ।।6.22.34।।
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महात्मनः great self, तस्यसागरस्य that Sagara's, तत् those, वचनम् words of request, श्रुत्वा hearing, सागरदर्शनात् on account of seeing the Sagara, दीप्तम् glowing, परम् supreme, तंशरम् that arrow, मुमोच let off.
On hearing the words of the request of Sagara and on account of seeing him, Rama let off the supreme arrow glowing (on the marauders).