On the day after the Great Disappointment — October 23 — Hiram Edson became convinced that "light would be given" and their "disappointment explained." Later that day, he was struck by the idea that the sanctuary to be cleansed was not the earth by fire, but rather something related to the heavenly sanctuary. This led him into an protracted and extensive study with O. R. L. Crosier and F. B. Hahn. They eventually concluded that, "The sanctuary to be cleansed in was not the earth or the church, but the sanctuary in heaven."