Valmiki Ramayana Sundara Kanda Sarga 39 Shloka 42
Original Shlokaततो वीरौ नरवरौ सहितौ रामलक्ष्मणौ। आगम्य नगरीं लङ्कां सायकैर्विधमिष्यतः।।5.39.42।।
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ततः then, वीरौ two heroes, नरवरौ both the princes, रामलक्ष्मणौ Rama and Lakshmana, सहितौ together, आगम्य on coming, लङ्कां नगरीम् to the city of Lanka, सायकैः with their arrows, विधमिष्यतः will blow away.
"Both the heroes, Rama and Lakshmana will come and blow up the city of Lanka with their unfailing arrows.