Valmiki Ramayana Sundara Kanda Sarga 48 Shloka 9
Original Shlokaइदं हि दृष्ट्वा मतिमन्महद्बलं कपेः प्रभावं च पराक्रमं च। त्वमात्मनश्चापि समीक्ष्य सारं कुरुष्व वेगं स्वबलानुरूपम्।।5.48.9।।
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मतिमन् O Intelligent one, त्वम् you, कपेः monkey's, इदम् this, महत् great, बलम् strength, प्रभावं च power also, पराक्रमं च and valour, दृष्ट्वा observing, आत्मनः your own, सारं चापि strength also, समीक्ष्य considering, स्वबलानुरूपम् in keeping with your own strength, वेगम् quickly, कुरुष्व do.
"O intelligent warrior measure the strength, power and valour of the monkey and your own strength carefully. Exercise your own strength and speed accordingly.