Valmiki Ramayana Ayodhya Kanda Sarga 85 Shloka 8
Original Shlokaतमेवमभिभाषन्तमाकाश इव निर्मलः। भरतश्श्लक्ष्णया वाचा गुहं वचनमब्रवीत्।।2.85.8।।
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आकाशः इव like the sky, निर्मलः tranquil, भरतः Bharata, एवम् thus, अभिभाषन्तम् talking, तं गुहम् addressing Guha, श्लक्ष्णया in gentle, वाचा voice, वचनम् words, अब्रवीत् said.
When he heard Guha thus speaking, Bharata who was as tranquil as the sky, said to him in a gentle voice.