Valmiki Ramayana Kishkindha Kanda Sarga 15 Shloka 8
Original Shlokaकाल्यमेतेन सङ्ग्रामं करिष्यसि च वानर। वीर ते शत्रुबाहुल्यं फल्गुता वा न विद्यते4.15.8।।
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वानर monkey, एतेन with him, काल्यम् tomorrow morning, सङ्ग्रामम् fight, करिष्यसि wish to wage, वीर hero, ते to you, शत्रुबाहुल्यम् respect enemy more, फल्गुता वा weak also, न विद्यते not become
'O monkey fight him only tomorrow morning. By this you are not going to prove your weakness or increase your respect for the enemy.