Clerical celibacy is the requirement in certain religions that some or all members of the clergy be unmarried. These religions consider that, outside of marriage, deliberate sexual thoughts, feelings, and behavior are sinful; clerical celibacy also requires abstention from these.
Within the Roman Catholic Church, clerical celibacy is mandated for all clergy in the Latin Church except deacons who do not intend to become priests. Exceptions are sometimes admitted for ordination to transitional diaconate and priesthood on a case-by-case basis for married clergymen of other churches or communities who become Catholics, but ordination of married men to the episcopacy is excluded (see Personal ordinariate). Clerical marriage is not allowed and therefore, if those for whom in some particular Church celibacy is optional (such as permanent deacons in the Latin Church) wish to marry, they must do so before ordination. Eastern Catholic Churches either follow the same rules as the Latin Church or require celibacy for bishops while allowing priestly ordination of married men.
Clerical celibacy is the discipline within the Catholic Church by which only unmarried men are ordained to the episcopate, to the priesthood (as a rule to which exceptions are sometimes made for individuals) in some autonomous particular Churches, and similarly to the diaconate, though in this last case exceptions exist not only for single individuals but for whole categories of people. The other autonomous particular Churches, the discipline applies only to ordination to the episcopate.
Chief of the Catholic particular Churches that follow this discipline is the Latin Church, but, among the Eastern Catholic Churches, at least the Ethiopic Catholic Church applies it also.
In this context, "celibacy" retains its original meaning of "unmarried". Though even the married may observe continence, abstaining from sexual intercourse, the obligation to be celibate is seen as a consequence of the obligation to observe perfect and perpetual continence for the sake of the Kingdom of heaven. Advocates see clerical celibacy as "a special gift of God by which sacred ministers can more easily remain close to Christ with an undivided heart, and can dedicate themselves more freely to the service of God and their neighbour."