Valmiki Ramayana Yuddha Kanda Sarga 107 Shloka 3
Original Shlokaराम राम महाबाहो शृणुगुह्यंसनातनम् । येनसर्वानरीस्वत्ससमरेविजयिष्यसे ।।6.107.3।।
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महाबाहो mighty armed, रामराम Rama Rama, सनातनम् eternal, गुह्यम् secret, शृणु hear, वत्स dear, येन because, समरे in war, सर्वान् all, अरीन् enemies, विजयिष्यसे which will enable you to win
"O mighty armed Sri Rama! Dear, hear this eternal secret (mantra) which will enable you to win all the enemies in war."