Valmiki Ramayana Sundara Kanda Sarga 52 Shloka 12
Original Shlokaअधर्ममूलं बहुदोषयुक्तमनार्यजुष्टं वचनं निशम्य। उवाच वाक्यं परमार्थतत्त्वं विभीषणो बुद्धिमतां वरिष्ठः।।5.52.12।।
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बुद्धिमताम् among the wise, वरिष्ठः foremost, विभीषणः Vibhishana, अधर्ममूलम् unrigteous, बहुरोषयुक्तम् mighty angry, अनार्यजुष्टम् not acceptable to noble souls, वचनम् words, निशम्य after hearing, परमार्थतत्त्वम् supreme truth, वाक्यम् these words, उवाच spoke.
On hearing his brother's harsh words spoken in tremendous anger, which were not acceptable to noble souls, wise Vibhishana again spoke these words of supreme truth: