Valmiki Ramayana Ayodhya Kanda Sarga 75 Shloka 45

अग्निदायके one who sets fire to human settlements, यत् पापम् sin of such act, गुरुतल्पगे violation of the preceptor's bed, यत् पापम् sin of such act, मित्रद्रोहे betraying a friend, यत् पापम् sin of such act, तत् पापम् sin of that act, प्रतिपद्यताम् be obtained.

May that one who counselled the exile of my esteemed brother acquire the sin in the same way as a person who sets fire to human settlements, violates the preceptors's bed and betrays his friend