Valmiki Ramayana Ayodhya Kanda Sarga 78 Shloka 22
Original Shlokaहन्यामहमिमां पापां कैकेयीं दुष्टचारिणीम्। यदि मां धार्मिको रामो नासूयेन्मातृघातकम्।।2.78.22।।
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धार्मिकः righteous, रामः Rama, मातृघातकम् slayer of mother, माम् me, न असूयेद्यदि if he were not to accuse me, दुष्टचारिणीम् a woman of wicked deeds, पापाम् sinful, इमां कैकेयीम् this Kaikeyi, अहम् I, हन्याम् would have killed.
If righteous Rama were not to accuse me of slaying a mother, I would have killed the sinful Kaikeyi of wicked deeds myself.