Valmiki Ramayana Aranya Kanda Sarga 5 Shloka 39
Original Shlokaततोऽग्निं स समाधाय हुत्वा चाज्येन मन्त्रवित्। शरभङ्गो महातेजाः प्रविवेश हुताशनम्।।3.5.39।।
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ततः then, महातेजाः effulgent, सः शरभङ्गः that Sarabhanga, अग्निम् fire, समाधाय after kindling with faggots, आज्येन with ghee, मन्त्रवित् knower of magical spells, हुत्वा च after offering oblations, हुताशनम् into the fire, प्रविवेश entered.
Then the effulgent Sarabhanga, knower of mantras (magical spells) kindled the fire with faggots and after offering oblations of ghee plunged in.