Valmiki Ramayana Sundara Kanda Sarga 11 Shloka 37
Original Shlokaपरदारावरोधस्य प्रसुप्तस्य निरीक्षणम्।।5.11.37।। इदं खलु ममात्यर्थं धर्मलोपं करिष्यति।
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प्रसुप्तस्य of those sleeping, परदारावरोधस्य of the inner chambers of others' wives, इदम् this, मम on my part, निरीक्षणम् observing them, अत्यर्थम् very much, धर्मलोपम् trangression of moral code, करिष्यति will lead to.
'Observing the wives of others in this manner in their inner chambers very much amounts to transgression of moral code by me'. ( thought he)