Celibacy (from calebs, 'unmarried'), a state opposed to the first and strongest natural law (Gen. i. 28), has from a variety of causes come to be regarded in certain religious systems as a condition of the most sublime self-sacrifice. The perpetual celibacy of the priests of Isis, and the chastity of the vestal virgins, are familiar instances. But nowhere was this sentiment so strongly and widely manifested as among the millions devoted to the religion of Buddha. The theories of oriental philosophers and the natural tendency of mystics did not fail to influence the early Christian churches, and led before long to the doctrine that virginity is a state in itself more excellent and more holy than the married life, and to the discipline which, in the Roman Church at least, imposed celibacy upon all priests and sacred ministers. The Old Testament is remarkably free from any tendency to exalt celibacy above matrimony. But although texts may be quoted on either side, the germs of the doctrine in question may be discovered in the New Testament. St Paul affirms it to be 'good for a man not to touch a woman,' and wishes that all men were celibate like himself (1 Cor. vii. 1, 7). Christ himself speaks mysterious words in commendation of those who 'have made themselves eunuchs for the kingdom of heaven's sake;' and the Lamb is followed on Mount Zion by 144,000 virgins, 'first-fruits unto God and unto the Lamb' (Rev. xiv. 1-5).
The apostolic writings, however, while they suggest the excellence of virginity in general, supply no ground for the law of clerical celibacy. In the first epistle to Timothy, the deacon as well as the bishop is told he must be the husband of one wife, and rule his household and his children well; and 'forbidding to marry' is reckoned among the 'doctrines of devils.' But a remote sanction for the later discipline has been sought for in the regulations of the Jewish priesthood. The Mosaic law forbade priests to marry divorced women or harlots, and enjoined continence upon all when preparing to offer sacrifice. Jerome argues that the Christian priest should offer sacrifice daily, and should therefore be perpetually continent; and Pope Siricius (385 A.D.) insists that marriage was permitted to the priest of the old law only because the sacerdotal order was then limited to the tribe of Levi, but now that the tribal restriction is removed, the license is abrogated also.
The ecclesiastical legislation on celibacy was developed gradually and unequally in the several parts of the church. In the 2d century it became a pious custom to make vows of chastity, and it was thought becoming in the higher clergy to renounce matrimony; and although there are examples of bishops and priests in the first three centuries living with their wives and begetting children, it has been confidently asserted that no instance can be quoted of a marriage contracted at this period after ordination. The obligations of the marriage contract were, however, considered sacred; and the Apostolic Canons impose the penalty of deposition on bishop, priest, or deacon, who should separate from his wife 'under the pretence of piety.' At the end of the 3d and beginning of the 4th century, marriage after ordination was prohibited by formal legislation. A further and important step was taken in the year 305 by the Spanish council of Elvira, which decreed that sacred ministers who were already married, should live in continence. At the Council of Nicaea an attempt was made to impose this new rule upon the whole church, but it was frustrated by the opposition of a venerable monk, Paphnutius, himself a celibate; and the law to this day has never been accepted in the Eastern Church. In the West, however, a series of synodal enactments and papal decrees established or renewed the more rigorous rule. But in no matter of ecclesiastical discipline must the distinction between theory and practice be more carefully observed. The clergy everywhere resisted the law, and resisted with considerable success. St Patrick, who tells us that his father and grandfather were in holy orders, when laying down rules in one of his Irish synods for the conduct of his clergy, directs that 'their wives should keep their heads covered.' In the province of Milan, indeed, the marriage of priests continued to be perfectly legal. Discipline and usage varied in different countries, but it may be safely said that for many countries the celibacy of the uncloistered clergy was little more than a pious fiction, until Hildebrand, afterwards Gregory VII., by his great influence and vigorous measures, secured a more strict observance of the rule.
From the 12th century (first and second Lateran Councils) a great change took place in ecclesiastical law. The marriage of priests was now declared to be not only sinful but invalid. It became henceforward difficult for any priest to justify his marriage on the plea that the prohibition of such marriage was abrogated by custom, or not binding under supposed exceptional circumstances. The clerical consorts became no longer wives but concubines; and, further, the priest who went through the marriage ceremony was held to commit a far greater crime than if he had contented himself with simple fornication. Yet in spite of all this the law was to a large extent set at defiance. In many parts of Europe it was a common thing for benefits to pass from father to son. Influential bishops obtained letters of legitimation for their children, and provided for them out of the property of the church. Avaricious princes and prelates made traffic of the concubinage of the lower clergy by levying a species of blackmail, under the name of fines, on the tacit understanding that the focaria, or occupant of the priest's hearth, should not be disturbed. At the time of the Council of Trent, the Emperor Charles, in the expectation that some relaxation would be made in the laws on the subject, permitted in 1548, by the arrangement known as the Interim, married priests to retain their wives until the council should come to a decision. The Emperor Ferdinand a little later (1562) urged upon the same council the abrogation of celibacy. But the Catholic reaction was too strong, and the council in November 1563 pronounced, 'If any one shall say that clerks constituted in holy orders, or regulars who have solemnly professed chastity, are able to contract matrimony, or that, being contracted, such matrimony is valid . . . let him be anathema.'
It should be observed, however, that in the United Greek Church Rome tolerates a married clergy—i.e. a man already married may be ordained priest, and continue to live with his wife, though continence is imposed upon him at certain times. It is the custom for the young candidate for orders to leave the seminary for a while to get a wife, and then return for ordination. If he should become a widower, he cannot of course marry again, and no married priest can be made a bishop. The bishops are therefore, as a rule, taken from the monasteries.
Since the Council of Trent, the observance of celibacy has been comparatively well maintained. This is especially true of those countries where the Catholic community is mixed with or surrounded by Protestant neighbours, and watched by a vigilant press. Away from the high-roads of civilisation, in Mexico, Brazil, and other parts, concubinage has again become the rule, less openly perhaps, but quite as obstinately as in the middle ages.
The moral loss or gain to the church from her discipline in this matter is a question of controversy which from time to time has been raised within her own communion. But the attention paid by biologists to the hereditary transmission of human faculties and dispositions has recently exhibited the effects of celibacy in a new light. Mr Galton has remarked that the Roman Church has acted as if she 'aimed at selecting the rudest portion of the community to be alone the parent of future generations.' The policy which attracts men and women of gentle natures fitted for deeds of charity, meditation, or study to the unfruitful life of the cloister and the priesthood, appears from this point of view to be 'singularly unwise and suicidal,' tending, as it must, though by imperceptible degrees, to the deterioration of the race. To the enforcing of this discipline in Spain, for example (coupled with the cutting off of independent thinkers by the Inquisition), Mr Galton attributes much of the decadence of the country during the last three centuries. In France, where the most promising lads of the village are successively picked out by the parish priest for the bishop's seminary, the process of elimination must in the long run tell upon the general character of the population. In small Catholic communities, again, where the priestly vocation is held in high esteem by the educated classes, and where mixed marriages are discountenanced, a similar result cannot fail to occur. The controversial literature on the matter is abundant. The most complete treatment of the subject, from the historical point of view, will be found in Sacerdotal Celibacy in the Christian Church, by Henry C. Lea (Philadelphia, 1867). See also MONACHISM.