Valmiki Ramayana Sundara Kanda Sarga 24 Shloka 21
Original Shlokaसीते पर्याप्तमेतावद्भर्तुः स्नेहो निदर्शितः।।5.24.21।। सर्वात्रातिकृतं भद्रे व्यसनायोपकल्पते
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सीते O Sita, भर्तुः your husband, स्नेहः love, निदर्शितः is shown, एतावत् to this extent, पर्याप्तम् it is enough, भद्रे auspicious lady, सर्वत्र everywhere, अतिकृतम् excess, व्यसनाय to adversity, उपकल्पते leads.
'O Sita you have shown your love for your husband to this extent. It is enough. O auspicious lady anything carried to excess leads to adversity.