Valmiki Ramayana Aranya Kanda Sarga 13 Shloka 14
Original Shlokaतत्र गत्वाऽऽश्रमपदं कृत्वा सौमित्रिणा सह। रमस्व त्वं पितुर्वाक्यं तथोक्तमनुपालयन्।।3.13.14।।
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त्वम् you, सौमित्रिणा सह along with Lakshmana, तत्र there, गत्वा after going, आश्रमपदम् hermitage, कृत्वा building, यथोक्तम् as told, पितुः father's, वाक्यम् words, अनुपालयन् while obeying, रंस्यसे you will enjoy.
Reaching there, you wikk build a hermitage with Lakshmana and enjoy your life given to the fulfilment of the pledge to the father.