Valmiki Ramayana Aranya Kanda Sarga 66 Shloka 17
Original Shlokaत्वमेव हि पुरा राम मामेवं बहुशोऽन्वशाः। अनुशिष्याद्धि को नु त्वामपि साक्षाद्बृहस्पतिः।।3.66.17।।
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राम Rama, पुरा in the past, त्वमेव you yourself, माम् to me, एवम् that way, बहुशः many times, अन्वशाः you instructed, हि indeed, साक्षात् personally, बृहस्पतिरपि even Brihaspati, को नु who indeed, त्वाम् to you, अनुशिष्यात् हि can teach you.
O Rama you yourself in the past have instructed me many times that way. Who can be your adviser in this matter ? You are indeed like Brihaspati.