Valmiki is celebrated as the poet harbinger in Sanskrit literature. He is the author of the epic Ramayana, based on the attribution in the text of the epic itself.He is revered as the Adi Kavi, which means First Poet, for he discovered the first śloka i.e. first verse, which set the base and defined the form to Sanskrit poetry. The Yoga Vasistha is attributed to him. A religious movement called Valmikism is based on Valmiki's teachings as presented in the Ramayana and the Yoga Vasistha. At least by the 1st century AD, Valmiki's reputation as the father of Sanskrit classical poetry seems to have been legendary. Ashvagosha writes in the Buddhacarita, "The voice of Valmiki uttered poetry which the great seer Chyavana could not compose." This particular verse has been speculated to indicate a familial relationship between Valmiki and Chyavana, as implied by the previous and subsequent verses.