Valmiki Ramayana Aranya Kanda Sarga 38 Shloka 13
Original Shlokaतं तदा दण्डकारण्ये यज्ञमुद्दिश्य दीक्षितम्। बभूवोपस्थितो रामश्चित्रं विष्फारयन्धनुः।।3.38.13।।
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तदा then, रामः Rama, दण्डकारण्ये in Dandaka forest, यज्ञम् Yagna, उद्दिश्य for the purpose, दीक्षितम् settled in rigorous religious discipline(vow), तम् him, उपस्थितः standing by, चित्रम् wonderful, धनुः bow, विष्फारयन् while stretching, बभूव became.
Then Rama was initiated for the protection of sacrifices and stood on guard, stretching his wonderful bow.