Valmiki Ramayana Yuddha Kanda Sarga 82 Shloka 20
Original Shlokaसनिवार्यपरानीकमब्रवीत्तान्वनौकसः ।।6.82.20।। हनूमान् सन्निवर्तध्वं न नस्साध्यमिदंबलम् ।
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सःहनूमान् that Hanuman, परानीकम् enemy army, निवार्य retreat, तान्वनौकसःhis own army, अब्रवीत् spoke, सन्निवर्तध्वम् no use defeating this army, इदम् thus, बलम् army, नः not, साध्यम् possible, न not
Hanuman made the enemy army retreat, and spoke to his own army," No use of defeating this army for us as our mission is not winning the army."