Valmiki Ramayana Yuddha Kanda Sarga 114 Shloka 29
Original Shlokaसर्वदासर्वभूतानांनास्तिमुत्युरलक्षणः । तवतावदयंमृत्युर्मैथिलीकृतलक्षणः ।।6.114.29।।
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सर्वभूतानाम् at all beings, सर्वदा always, अलक्षणः without reason, मृत्युः death, नास्ति not, तवतावत् to you also, अयम् this, मैथिलीकृतलक्षणः on account of getting Mythili
"Death does not happen without reason for any being. To you this happened because of getting Mythili."