Valmiki Ramayana Ayodhya Kanda Sarga 52 Shloka 67
Original Shlokaसोऽहं गृहीत्वा नियमं तपस्वि जनभूषणम्। हितकामः पितुर्भूयः सीताया लक्ष्मणस्य च।।2.52.67।। जटाः कृत्वा गमिष्यामि न्यग्रोधक्षीरमानय।
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सः अहम् that I, तपस्विजनभूषणम् the adornment of ascetics, नियमम् prescribed austerities, गृहीत्वा accepting, पितुः father's, भूयः also, सीतायाः Sita's, लक्ष्मणस्य च also Lakshmana's, हितकामः seeking their good, जटाः कृत्वा having matted my locks of hair, गमिष्यामि shall go, न्यग्रोधक्षीरम् latex of banyan tree, आनय fetch.
Seeking the welfare of my father, Sita and Lakshmana I shall enter the forest with matted hair and practise the prescribed austerities which are the adornments of ascetics. Do fetch me the sap of a banyan tree.