Valmiki Ramayana Yuddha Kanda Sarga 37 Shloka 33
Original Shlokaनचैवमानुषंरूपंकार्यंहरिभिराहवे ।।6.37.33।। एषाभवतुसंङञान् युद्धेऽस्मिन् वानरेबले ।
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आहवे in battle, हरिभिः monkeys, मानुषं human, रूपम् form, नचैवम् not have, कार्यम् task, अस्मिन् our, युद्धे war, वानरे Vanaras, बले, एषा in that way, संज्ञा sign, भवतु let it be.
"In the battle like this at present Vanaras should not be in the semblance of humans. Let this be our sign."