Valmiki Ramayana Ayodhya Kanda Sarga 21 Shloka 51
Original Shlokaयथैव ते पुत्र पिता तथाऽहं गुरु स्स्वधर्मेण सुहृत्तया च। न त्वाऽनुजानामि न मां विहाय सुदुःखितामर्हसि गन्तुमेवम्।।2.21.51।।
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पुत्र O my son, स्वधर्मेण by virtue of one's own duty, सुहृत्तया च out of affection, ते your, पिता father, यथैव as he is to you, तथा like that, अहम् I, गुरुः preceptor, त्वा you, न अनुजानामि do not permit, सुदुःखिताम् highly distressed, माम् me, विहाय leaving, एवम् in this manner, गन्तुम् to go, नार्हसि does not behove you.
By virtue of my own duty and affection towards you, O my son I am as much your preceptor as your father is. I will not grant you permission. You should not go, leaving me deeply distressed.