Valmiki Ramayana Aranya Kanda Sarga 13 Shloka 12
Original Shlokaततोऽब्रवीन्मुनिश्रेष्ठश्श्रुत्वा रामस्य तद्वचः। ध्यात्वा मुहूर्तं धर्मात्मा धीरो धीरतरं वचः।।3.13.12।।
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ततः thereafter, धर्मात्मा a righteous soul, धीरः cool, मुनिश्रेष्ठः best among sages, रामस्य Rama's, तत् that, वचः words, श्रुत्वा on hearing, मुहूर्तम् for a while, ध्यात्वा after thinking, धीरतरम् more solemn, वचः word, अब्रवीत् uttered.
On hearing the words of Rama, Agastya, the best among the sages, coolheaded and righteous, thought a while and uttered these words coolly :