Valmiki Ramayana Sundara Kanda Sarga 52 Shloka 13
Original Shlokaप्रसीद लङ्केश्वर राक्षसेन्द्र धर्मार्थयुक्तं वचनं शृणुष्व। दूतानवध्यान् समयेषु राजन् सर्वेषु सर्वत्र वदन्ति सन्तः।।5.52.13।।
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लङ्केश्वर lord of Lanka, राक्षसेन्द्र king of demons, प्रसीद calm down, धर्मार्थयुक्तम् which is the essence of dharma and artha, वचनम् words, शृणुष्व listen, राजन् O king, सर्वेषु for all, समयेषु conditions, सर्वत्र for all places, दूतान् emissaries, अवध्यान् not to be killed, सन्तः elders, वदन्ति have declared.
"O lord of Lanka O king of demons be pleased to listen to my words which are the essence of dharma and artha. The elders have declared that the emissaries should not be killed by any means.