Valmiki Ramayana Kishkindha Kanda Sarga 18 Shloka 5
Original Shlokaअपृष्ट्वा बुद्धिसम्पन्नान्वृद्धानाचार्यसम्मतान्। सौम्य वानरचापल्यात्किं मावक्तुमिहेच्छसि4.18.5।।
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बुद्धिसम्पन्नान् endowed with intelligence, आचार्यसम्मतान् which carries the approval of teachers, वृद्धान् elderly, अपृष्ट्वा without consulting, त्वम् you,सौम्य gentle one, माम् me, वानरचापल्यात् from frivolousness of a monkey, इह here, वक्तुम् for talking this way, इच्छसि you wish.
'O gentle Vali why do you speak with monkeyish frivolousness, without consulting the elders and teachers endowed with intelligence?