Valmiki Ramayana Aranya Kanda Sarga 9 Shloka 18
Original Shlokaतस्यैव तपसो विघ्नं कर्तुमिन्द्रश्शचीपतिः।।3.9.18।। खङ्गपाणिरथागच्छदाश्रमं भटरूपधृत्।
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अथ then, शचीपतिः husband of Sachi, इन्द्रः Indra, तस्यैव his only, तपसः penance, विघ्नम् obstruction, कर्तुम् to do, भटरूपधृत् in the guise of an attendant, खङ्गपाणिः sword in hand, आश्रमम् to the hermitage, आगच्छत् came.
Once Indra, husband of Sachi, came to his hermitage in the guise of an attendant, sword in hand, in order to hinder his penance.