Valmiki Ramayana Ayodhya Kanda Sarga 117 Shloka 5
Original Shlokaसोऽत्रेराश्रममासाद्य तं ववन्दे महायशाः। तं चापि भगवानत्रिः पुत्रवत्प्रत्यपद्यत।।2.117.5।।
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महायशाः illustrious one, सः रामः that Rama, अत्रेः Atri's, आश्रमम् hermitage, आसाद्य having reached, तम् to that sage, ववन्दे prostrated, भगवान् the revered, अत्रिः Atri, अपि also, तं him as well, पुत्रवत् like a son, प्रत्यपद्यत received.
Having reached the hermitage of the revered sage Atri, illustrious Rama prostrated before him and Atri also received him as his son.