Valmiki Ramayana Yuddha Kanda Sarga 79 Shloka 18
Original Shlokaकत्थसेकिंवृथारक्षो बहून्यसदृशानिते । न रणेशक्यतेजेतुंविनायुद्धेनवाग्भलात् ।।6.79.18।।
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रक्षः Rakshasa, असदृशानि in What can't be accomplished, बहूनि many, वृथा wasteful, किंकत्थसे why indulge, युद्धेनविना without war, वाग्भलात् force of speech, रणे in war, जेतुम् victory, ते by you, न शक्यम् not possible
"Rakshasa! Why so much of wasteful talk about What you can't accomplish? Victory is not possible on the battlefield with your force of speech"