Valmiki Ramayana Sundara Kanda Sarga 52 Shloka 1
Original Shlokaतस्य तद्वचनं श्रुत्वा वानरस्य महात्मनः। आज्ञापयद्वधं तस्य रावणः क्रोधमूर्छितः।।5.52.1।।
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महात्मनः of the great, तस्य वानरस्य of vanara's, तत् वचनम् the speech, श्रुत्वा on hearing, रावणः Ravana, क्रोधमूर्छितः overwhelmed with anger, तस्य his, वधम् slaying, आज्ञापयत् ordered.
Hearing the great vanara's speech, Ravana overwhelmed with anger ordered the execution of Hanuman. Vibhishana advises Ravana against slaying of an emissary -- elaborates on the code of conduct of a king