Valmiki Ramayana Sundara Kanda Sarga 24 Shloka 26
Original Shlokaअग्नेः स्वाहा यथा देवी शची वेन्द्रस्य शोभने।।5.24.26।। किं ते रामेण वैदेहि कृपणेन गतायुषा।
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शोभने O beautiful one, अग्नेः for fire, देवी queen, स्वाहा यथा like Swaha, इन्द्रस्य Indra's, शचीव like Sachi, वैदेहि Vaidehi, कृपणेन a pitiable, गतायुषा whose life span is to end soon, रामेण with Rama, किम् what is the use?
O beautiful Sita Just like Swaha, queen to the Firegod and Sachi to Indra, accept Ravana. Why are you still thinking of Rama who is helpless and whose life span is coming to an end soon.