Valmiki Ramayana Ayodhya Kanda Sarga 18 Shloka 37
Original Shlokaसप्त सप्त च वर्षाणि दण्डकारण्यमाश्रितः। अभिषेकमिमं त्यक्त्वा जटाजिनधरो वस।।2.18.37।।
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इमम् अभिषेकम् this consecration, त्यक्त्वा having forsaken, जटाजिनधर: with matted hair and deerskin, दण्डकारण्यम् आश्रितः taking refuge in Dandaka forest, सप्त सप्त च वर्षाणि seven and seven (fourteen) years, वस live.
Forsake this consecration, wear matted locks and deerskin and take refuge in Dandaka forest for fourteen years.