Valmiki Ramayana Sundara Kanda Sarga 1 Shloka 113
Original Shlokaराघवस्य कुले जातैरुदधिः परिवर्धितः। स त्वां रामहिते युक्तं प्रत्यर्चयति सागरः।।5.1.113।।
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उदधिः the ocean, राघवस्य of Raghava's, कुले in the family, जातैः by those born, परिवर्धितः is extended, सः सागरः that Sagara, रामहिते for the service of Rama, युक्तम् endowed with, त्वाम् you, प्रत्यर्चयति honour in return.
"The son of Rama's family, Sagara, has extended the ocean in the past.It is most appropriate that he (the god of the sea) honours you in return as you have set out in the service of Rama.