Valmiki Ramayana Yuddha Kanda Sarga 36 Shloka 13
Original Shlokaसतुतीर्त्वार्णवंरामस्सहवानरसेनया । प्रतिजानामितेसत्यंनजीवन्प्रतियास्यति ।।6.36.13।।
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सःराघवः that Raghava, वानरसेवयासह along with Vanara army, आर्णवम् sea, तीर्त्वा crossed water, जीवन् with life, नप्रतियाप्यति not going back, ते, सत्यम् true, प्रतिजानामि will not return back.
"Rama having crossed the sea with his Vanara army will not go back with life. It is true."