Valmiki Ramayana Sundara Kanda Sarga 37 Shloka 40
Original Shlokaतव सत्त्वं बलं चैव विजानामि महाकपे। वायोरिव गतिं चैव तेजश्चाग्नेरिवाद्भुतम्।।5.37.40।।
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महाकपे O great monkey, तव your, सत्त्वम् strength, बलं चैव and power, वायोरिव like the Windgod's, गतिम् speed, आग्नेरिव like fire's, अद्भुतम् astonishing, तेजश्च splendour, विजानामि I have understood
"O great monkey I have understood your strength and power. Your speed is like the Windgod's and your power is astonishing and splendid.