Valmiki Ramayana Bala Kanda Sarga 64 Shloka 17
Original Shlokaबभूवास्य मनश्चिन्ता तपोऽपहरणे कृते । नैव क्रोधं गमिष्यामि न च वक्ष्ये कथञ्चन।।1.64.17।।
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तपोपहरणे कृते having been deprived of his ascetic merit, अस्य for him, मनश्चिन्ता बभूव thought arose in his mind, क्रोधम् anger, नैव गमिष्यामि never shall I obtain, कथञ्चन in what so ever manner, न च वक्ष्ये I shall not speak also.
Having been deprived of his ascetic merit, he resolved not to lose his temper nor ever breathe a word".