Valmiki Ramayana Bala Kanda Sarga 68 Shloka 11
Original Shlokaअस्मै देया मया सीता वीर्यशुल्का महात्मने। प्रतिज्ञां कर्तुमिच्छामि तदनुज्ञातुमर्हसि।।1.68.11।।
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वीर्यशुल्का the 'Reward for Prowess', सीता Sita, अस्मै to this, महात्मने eminent one, मया by me, देया fit to be given, प्रतिज्ञाम् vow, कर्तुम् to fufill, इच्छामि desiring, तत् for that reason, अनुज्ञातुम् to give your consent, अर्हसि behoves of you.
Sita is fit to be given in marriage to this eminent Rama as a reward for his prowess. I request you to give your consent to fulfil my vow.