Valmiki Ramayana Yuddha Kanda Sarga 18 Shloka 8
Original Shlokaअनधीत्यचशास्त्राणिवृद्धाननुपसेव्यच । नशक्यमीदृशंवक्तुंयदुवाचहरीश्वरः ।।6.18.8।।
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हरीश्वरः Lord of monkeys, यत् that which, उवाचह: has been said, ईदृशम् in this way, वक्तुम् to speak, शास्त्राणि: sastras, अनधीत्य: without studying, वृद्दान् elders, अनुपसेन्यच: to one who has served, नशक्यम् not possible.
"That which has been spoken by the Lord of monkeys in this way is not possible for one who has not studied sastras or served the elders."