Valmiki Ramayana Bala Kanda Sarga 2 Shloka 31
Original Shlokaमच्छन्दादेव ते ब्रह्मन् प्रवृत्तेयं सरस्वती । रामस्य चरितं सर्वं कुरु त्वमृषिसत्तम ।।1.2.31।।
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ब्रह्मन् OBrahmarshi, ते इयम् your this, सरस्वती speech, मच्छन्दादेव at my will, प्रवृत्ता originated, ऋषिसत्तम O most excellent ascetic, रामस्य Rama's, चरितम् history, सर्वम् in entirety, त्वम् you, कुरु compose.
"OBrahmarshi, at my will, this speech had originated from you. Most excellent ascetic, compose the history of Rama in its entirety (in this metre).