➀ Size Length: Approximately 24.5cm Width: Approximately 9.5cm "Jōsai Daishi" (常済大師) of the Sōtō Zen sect This is the posthumous title (okurina) of Keizan Jōkin (also known as Zen Master Keizan), a monk who laid the foundation of the Sōtō Zen sect and spread Zen widely among the masses, considered the founder (taiso). Photographs of the side hangings "Shōyō Daishi and Jōsai Daishi" of the Sōtō Zen sect are enshrined to the left (left side attendant) of the principal image (Shaka Nyorai), and are revered as the two great patriarchs of the Sōtō Zen sect along with Koso Dōgen Zenji (Shōyō Daishi).