 In the Middle Ages, reading and writing were almost exclusively the domain of the priestly class, and this is the reason for the close relationship of these words.Within Christianity, especially in Eastern Christianity and formerly in Western Roman Catholicism, the term "cleric" refers to any individual who has been ordained, including deacons, priests, and bishops.In Latin Roman Catholicism, the tonsure was a prerequisite for receiving any of the minor orders or major orders before the tonsure, minor orders, and the subdiaconate were abolished following the Second Vatican Council.