Valmiki Ramayana Aranya Kanda Sarga 4 Shloka 12
Original Shlokaइत्युक्त्वा लक्ष्मणं रामः प्रदरः खन्यतामिति। तस्थौ विराधमाक्रम्य कण्ठे पादेन वीर्यवान्।।3.4.12।।
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वीर्यवान् courageous one, रामः Rama, लक्ष्मणम् to Lakshmana, इति thus, प्रदरः crevice, खन्यताम् may be dug up, इति thus, उक्त्वा having said, विराधम् Viradha, पादेन with his foot, कण्ठे on his neck, आक्रम्य holding firmly there, तस्थौ stood.
Courageous Rama standing there put his foot firmly on the neck of Viradha and said to Lakshmana,' Dig up a crevice'.