Valmiki Ramayana Yuddha Kanda Sarga 9 Shloka 16
Original Shlokaनतुक्षमंवीर्यवतातेनधर्मानुवर्तिना । वैरंनिरर्थकंकर्तुंदीयतामस्यमैथिली ।।6.9.16।।
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वीर्यवता: valorous one, धर्मानुवर्तिना: follower of dharma, तेन: his, निरर्थकम् useless, वैरम् enmity, कर्तुम् to have, नतुक्षमम् not good for us, मैथिली: Mythili, अस्य: to him, दीयताम् give away.
"To have enmity with a valorous one, a follower of dharma, is useless and not good for us. Give away Mythili to him (Rama)."