Valmiki Ramayana Aranya Kanda Sarga 9 Shloka 23
Original Shlokaततस्सरौद्रेऽभिरतः प्रमत्तोऽधर्मकर्शितः।।3.9.23।। तस्य शस्त्रस्य संवासाज्जगाम नरकं मुनिः।
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ततः then, तस्य of that, शस्त्रस्य संवासात् in association with the weapon, रौद्रे in a violent mood, अभिरतः always involved, सः that, मुनिः sage, प्रमत्तः in excitement अधर्मकर्शितः dragged in unrighteous ways, नरकम् to hell, जगाम went.
By association with the sword, he developed a violent attitude. And in that habitual state of excitement he was dragged into unrighteous ways which (ultimately) took him to hell.