Valmiki Ramayana Aranya Kanda Sarga 65 Shloka 4
Original Shlokaपुरा भूत्वा मृदुर्दान्तस्सर्वभूतहिते रतः। न क्रोधवशमापन्नः प्रकृतिं हातुमर्हसि।।3.65.4।।
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पुरा in the past, मृदुः gentle, दान्तः selfrestrained, सर्वभूतहिते in the welfare of all beings, रतः as engaged, भूत्वा after being, क्रोधवशम् under the spell of anger, आपन्नः attaining, प्रकृतिम् natural form, हातुम् to give up, नार्हसि do not behove.
Earlier you were gentle, self restrained and engaged in the welfare of all beings. (Now) it is not proper for you to give up your natural composure in anger.