According to a legend about the founding of Hase-dera Temple, in the 720s a big sacred tree washed up on the banks of the Hatsuse River and brought down a great curse, causing fear among the villagers, who asked the founder, Tokudo, to make a statue of the Bodhisattva Kannon from the sacred tree, which was the root of curse, and the statue was enshrined on Mt. Hatsuse near the village.
長谷寺の本尊像については、神亀年間（720年代）、近隣の初瀬川に流れ着いた巨大な神木が大いなる祟りを呼び、恐怖した村人の懇願を受けて開祖徳道が祟りの根源である神木を観音菩薩像に作り替え、これを近くの初瀬山に祀ったという長谷寺開山の伝承がある。