Valmiki Ramayana Yuddha Kanda Sarga 48 Shloka 18
Original Shlokaनहिदृष्टिपथंप्राप्यराघवस्यरणेरिपुः । जीवन्प्रन्तिवर्तेतयद्यपिस्यान्मनोजवः ।।6.48.18।।
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रिपुः enemy, मनोजवः who is endowed with speed in thought, स्याद्यद्यपि if seen, रणे in war, राघवस्य by Rama, दृष्टिपथम् range of sight, प्राप्य happens, जीवन् life, नप्रन्तिवर्ततेहि not go alive.
"Even if the enemy is endowed with speed of thought, if he comes in the range of Rama's sight, he will not go alive."