Valmiki Ramayana Yuddha Kanda Sarga 22 Shloka 48
Original Shlokaअयंहिसागरोभीमस्सेतुकर्मदिदृक्ष्याः । ददौदण्डभयाद्गाधंराघवायमहोदधिः ।।6.22.48।।
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भीमः fearsome, अयंहि I also, सागरः ocean, महोदधिः mighty ocean, दण्डभयात् fear of punishment, सेतुकर्मदिदृक्ष्या to witness the building of a bridge, राघवाय to Rama, गाधम् place, ददौ allowed a passage.
This fearsome ocean of mighty Sagara (dug by Sagara) then allowed a passage for Rama, out of fear of punishment and also to witness the building of a bridge.