follower of a religion; believer; Jōdo Shinshū practitioner
Often refers specifically to followers of Jōdo Shinshū (True Pure Land Buddhism), but can be used more broadly for religious followers. The term carries a slightly formal or traditional tone.
He is a devout follower and goes to the temple every morning to pray.
There are many Jōdo Shinshū followers in this area.
門徒 refers to a believer of a Buddhist sect, whereas 使徒 is specifically a Christian apostle, so the two should not be swapped despite both meaning 'religious follower'.
ignorance of Jōdo Shinshū followers
Composed of 門 (gate, sect) and 徒 (follower, disciple). The term historically referred to disciples of a particular Buddhist school, and its usage became strongly associated with Jōdo Shinshū.