Although the origins of this statue are unknown, judging from its unique attire—its Buddhist surplice over a secular outer robe— it is thought to be Izusan Gongen, the avatar of hot springs in the Mount Izu region. A recent dendrochronological examination has shown that the wood came from a tree that was cut down in 1145 at the earliest. There is a sense of a provincial style to its execution.  
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This statue was enshrined in Izusan-jinja Shrine in Atami city, Shizuoka Prefecture. It was also called as Hashiriyu gongen which was deified the deity of the hot spring (“Hashiriyu“ is another way of saying hot spring in Japanese). The statue was decorated with a formal headpiece (eboshi) and Buddhist robe (kesa) layered on dayware court dress (nōshi) and male skirt (hakam). The divine figure was expressed as devotee of the Buddhism representing a syncretism of Japanese Shitōism and Buddhism.
 
Shigeki Iwata 
Masterworks from the Nara Buddhist Sculpture Hall at the Nara National Museum. Nara National Museum, 2010, p.139, no.146.