Valmiki Ramayana Sundara Kanda Sarga 53 Shloka 2
Original Shlokaसम्यगुक्तं हि भवता दूतवध्या विगर्हिता। अवश्यं तु वधादन्यः क्रियतामस्य निग्रहः।।5.53.2।।
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भवता by you, सम्यक् very well, उक्तं हि indeed spoken, दूतवध्या killing of emissary, विगर्हिता is censured, वधात् other than killing, अन्यः other, निग्रहः punishment, अस्य his, अवश्यम् surely, क्रियताम् may be done.
"Indeed, you have spoken very well.Killing of emissary is censured (in sastras). Surely we will impose suitable punishment other than killing.