Valmiki Ramayana Aranya Kanda Sarga 38 Shloka 12
Original Shlokaएवमुक्त्वा तु स मुनिस्तमादाय नृपात्मजम्। जगाम परमप्रीतो विश्वामित्रस्स्वमाश्रमम्।।3.38.12।।
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सः that, विश्वामित्रः मुनिः sage Visvamitra, एवम् in that way, उक्त्वा having said, परमप्रीतः very happily, तम् him, नृपात्मजम् prince Rama, आदाय after taking, स्वम् his, आश्रमम् hermitage, जगाम went.
Sage Visvamitra saying so took the son of the king and went back very happily to his hermitage.