Ramayana
ततः पितरमामन्त्र्य इक्ष्वाकुं हि मनोः सुतम् । वसिष्ठं वरयामास पूर्वं ब्रह्मर्षिसत्तमम् ॥ 7-55-8 ॥
Then, having taken leave of his father Ikshvaku, the son of Manu, he first chose Vasishtha, the most excellent of the Brahmin sages, as his priest.
english translation