Valmiki Ramayana Ayodhya Kanda Sarga 23 Shloka 8
Original Shlokaसन्ति धर्मोपधा श्लक्ष्णाः धर्मात्मन्किं न बुध्यसे।।2.23.8।। तयोस्सुचरितं स्वार्थं शाठ्यात्परिजिहीर्षतोः।
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धर्मात्मन् O virtuous one, शाठ्यात् perfidiously, स्वार्थम् for selfish ends, सुचरितम् of good conduct, परिजिहीर्षतोः for both of them repudiating, तयोः of both of them, श्लक्ष्णाः soft ones, धर्मोपधा acts of deception in the guise of righteousness, सन्ति exist, किं why, न बुध्यसे do you not know.
Why don't you realise, O virtuous one that there are soft means of creating hindrances in their plan without trangressing dharma. You know dharma. Why don't you understand that their acts of deception wear the guise of dharma?