Valmiki Ramayana Ayodhya Kanda Sarga 106 Shloka 10
Original Shlokaकथं दशरथा ज्जात श्शुद्धाभिजनकर्मणः। जानन् धर्ममधर्मिष्ठं कुर्यां कर्म जुगुप्सितम्।।2.106.10।।
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शुद्धाभिजनकर्मणः of noble race and righteous deeds, दशरथात् from Dasaratha, जातः born of, धर्मम् righteousness, जानन् knowing, अधर्मिष्ठम् unrighteous, जुगुप्सितम् reprehensible, कर्म deed, कथम् how, कुर्याम् shall I do?.
How shall I, born to Dasaratha of noble race and righteous deeds, with the knowledge of dharma, do such a reprehensible and unrighteous deed?