 सुमहत्यपराधेऽपि दूतस्यातुलविक्रमः।विरूपकरणं दृष्टं न वधोऽस्तीति शास्त्रतः।। 
 O Ravana of immeasurable courage even if the emissary has done any kind of harm he may be mutilated but not murdered. Nowhere do the sastras allow killing of an ambassador. 