Buddhist services for the dead are usually held seven times and each is held every seven days; each service is held to ask Juo to decrease transgression of the dead; it is considered that religious services for the repose of the soul of the dead are done for the additional three trials so that Juo will not fail to rescue all the dead.
なお、仏事の法要は大抵七日ごとに七回あるのは、審理のたびに十王に対し死者への減罪の嘆願を行うためであり、追加の審理の三回についての追善法要は救い損ないをなくすための受け皿として機能していたようだ。