A shinzō is a statue of a kami, or Shinto deity, in corporeal form. Here, the kami appears with a shaved head as a Buddhist priest. The statue’s hands are missing, but their likely positioning can be assumed to have resembled the iconography of Hachiman in the Guise of a Priest exemplified by a statue at Yakushiji. Such images of this kami started appearing in the early part of the Heian period (794–1185). Its stern expression and the sharp carving of its ears are characteristic of tenth-century Buddhist sculpture. 
Audio guide 

This is a statue of a kami, a Shinto deity (shinzō), but with its shaved head it takes the form of a Buddhist priest. From what remains of the arms, one can surmise that they were posed similarly to the statues of Hachiman in the guise of a monk made in the early Heian period (794–1185). An important example of such an image is enshrined at Yakushiji Temple. There are many tenth-century statues with similarly stern expressions and strikingly sculpted ears.
 
YAMAGUCHI RyusukeEnglish by Mary Lewine 
Buddhist Art Paradise: Jewels of the Nara National Museum. Nara National Museum, 2021.7, p.336, no.164.