Sosho entered Todai-ji Temple in1214, and became a disciple of Dosho, receiving Tokudo (enter the Buddhist priesthood) and dwelled at Todai-ji Temple Chuin (central temple): Sonsho-in. He successively held the posts of Sogo (the priestly administrative post) and Gon Daisozu (the provisional highest grade that can be held by one who has reached the second highest rank in the hierarchy of Buddhist priests), then he was appointed as Betto (the head priest) of Todai-ji Temple in 1260. He made an effort to revive the old Buddhism, and was seriously involved with Miroku (Maitreya) Belief influenced by Jokei at Mt.Kasgi in 1230, then wrote Mirokunyorai Kanno Sho (The selection of the influence of Mirokunyorai) in1235. Sosho was appointed Gonsojo (the lowest grade that can be held by one who has reached the highest rank in the hierarchy of Buddhist priests) in 1269. There are still many manuscripts in Sosho's own handwriting in Todai-ji Temple, which clearly show his profound knowledge. However, among them there are materials which indicate the corruption of some of the monks at the time, indulging in alcohol drinking and sodomy.