Reverend Kōsai was a priest belonging to the Rinzai sect of Zen Buddhism who was famous for preaching in a way that was easily understandable to a wide range of people. He was active during the early Edo period (1603–1868) and was the founder of Kōrinji Temple. 

This statue was produced during the Edo period, it has been carefully colored and the face carved with great skill to bring out the personality of the priest. It can be said to be representative of the statues produced during this era.

The restoration consisted of careful cleaning while simultaneously preventing flaking and touching up the coloring where flaking has detracted from the statue’s countenance. As a result of this restoration, the work was returned to something approaching its original bright color.