Valmiki Ramayana Aranya Kanda Sarga 37 Shloka 18
Original Shlokaअप्रमेयं हि तत्तेजो यस्य सा जनकात्मजा। न त्वं समर्थस्तां हर्तुं रामचापाश्रयं वने।।3.37.18।।
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सा she, जनकात्मजा Sita, daughter of Janaka, यस्य whose, तत् that, अप्रमेयम् immeasurable, तेजः हि is the power, वने in the forest, रामचापाश्रयम् under the refuge of Rama's bow, ताम् herself, हर्तुम् to abduct, त्वम् you, समर्थः competent, न not.
Immeasurable indeed is the power of Rama to whom Sita, daughter of Janaka belongs. You are not competent to kidnap her, for she is under the refuge of Rama's bow in the forest.