Valmiki Ramayana Bala Kanda Sarga 13 Shloka 5
Original Shlokaतथेति च स राजानमब्रवीद्द्विजसत्तमः। करिष्ये सर्वमेवैतद्भवता यत्समर्थितम्।।1.13.5।।
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द्विजसत्तम: foremost among brahmins, स: sage Vasishta, भवता by you, यत् which ever, समर्थितम् as decided by you, एतत् that, सर्वम् all, तथा in that manner, करिष्ये will be performed, इति thus, राजानम् to the king, अब्रवीत् said.
The great among brahmins answered him saying "I shall do everything as proposed by you".