Valmiki Ramayana Ayodhya Kanda Sarga 37 Shloka 1
Original Shlokaमहामात्रवचः श्रुत्वा रामो दशरथं तदा। अभ्यभाषत वाक्यं तु विनयज्ञो विनीतवत्।।2.37.1।।
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विनयज्ञः knower of politeness, रामः Rama, महामात्रवचः minister's words, श्रुत्वा having heard, तदा then, दशरथम् Dasaratha, विनीतवत् humbly, वाक्यम् words, अभ्यभाषत spoke.
On hearing the minister, Rama who knew how to be polite spoke these words to Dasaratha humbly: Rama puts on bark--Vasistha blames Kaikeyi--says Sita was not ordained to wear bark.