Early Practise (§ 1).
The Lesser and Greater Excommunication (§ 2).
Various Legal Provisions (§ 3).
Changes Introduced by the Reformation (§ 4).

1. Early Practise.

Excommunication is the exclusion of an offender from full church fellowship, which may occur as a means of discipline in varying degrees. On the basis of various passages of Scripture (Matt. xvi. 19; xviii. 18; John xx. 23; I Thess. v. 14; James v.16; I John i. 8 sqq.; v. 16; II Cor. v. 18 sqq.; for the old Testament ban, see LAW, HEBREW, CIVIL AND CRIMINAL), the Church of the earliest times undertook to punish grievous sinners by such exclusion, and either refused entirely to restore them to its fellowship or restored them only after they had attested their sorrow by penance (q.v.). After the Councils of Ancyra (314) and Nicæa (325), four stages of penance developed through which the offender had to pass. During the first year he lay prostrate and weeping in the vestibule of the church and begged those entering in to pray for him (Gk. prosklausis; Lat. fletus). Next, commonly for three years, he had a place in the back of the church, with the unbaptized catechumens, where he was allowed to hear the reading of the Scriptures (akroasis; auditio). Then he was allowed to enter the body of the church, and to pray prostrate, while the bishop and the faithful interceded for him (hypoptsis; genuflexio, substratio). After further penitential exercises, he was allowed to pray standing, with the rest of the congregation, and to be present at the most sacred portion of the liturgy, the missa fidelium, from which the catechumens were excluded (systasis; consistentia). Only after the completion of this long process was he restored to full communion. Originally this discipline was applied also to sins which had given no public scandal, until Pope Leo I. forbade them to be publicly confessed (450), after which public penance was only applied to open sins the graver ones in the manner described, the lesser ones without exclusion from the fellowship of the faithful, but still so as to atone for public scandal, and covering the exclusion from the missa fidelium. Both of these methods are called pænæ medicinales by Augustine; their application belonged to the bishop, whose action must be recognized by his brother bishops, and could be reversed only by himself.

2. The Lesser and Greater Excommunication.

In the Frankish kingdom, after the institution of the Synodal Courts (q.v.), penitential discipline was placed in their charge, when once the testes synodales had established the existence of an open scandal. By degrees the old distinct stages of penance, which had at first been accepted also in the West, fell into disuse in the Frankish kingdom. Finally public penance practically ceased, and the exclusion from the sacraments became regularly (as it had been exceptionally) an independent measure of discipline, becoming known as the lesser excommunication, while the old exclusion from all blessings and graces of the Church was called the greater. In the view of the canon law these form the general means used by the ecclesiastical body for the maintenance of its discipline. Both presuppose a cause which is both public and grave. None can be excommunicated but living, baptized persons who have the use of reason. The bishop has the right of excommunication over those who belong to his diocese, though his sentence is valid also outside of it; a prelate with quasiepiscopal jurisdiction, such as a papal legate, has it in the territory for which he is commissioned; and the pope for the Church at large. The power of reconciliation is vested in the same person, and it requires as a condition the promise of obedience for the future.

3. Various Legal Provisions.

Excommunication is either juris or hominis, i.e., prescribed by law or pronounced at the decision of an authorized person in a case not explicitly covered by the law. It is divided again into excommunicatio latæ sententiæ, where it takes effect ipso facto upon the commission of a specified offense, or ferendæ sententiæ, where it follows an express judicial decision. The latter class requires two warnings at least. Ignorance of the law excuses from the former, and to be effective it must be definitely proclaimed. The lesser excommunication deprives a person of the sacraments; the greater cuts him off from all rights--the mass may not be celebrated in his presence, he can not hold a benefice, exercise jurisdiction, or take part in an ecclesiastical election, and Christian burial is denied him; intercourse with the faithful is prohibited except in certain specified cases. Since the time of Gregory IX. the term Anathema (q.v.) has been applied to the solemn declaration of the greater excommunication (cf. the form in the Pontificale Romanum).

4. Changes Introduced by the Reformation.

The canon law expects that the State will give effect on its side to the social consequences of exclusion from Christian fellowship. The extent to which the civil governments of the Middle Ages were subservient to the power of the Church over society may be seen in the way they responded to such appeals; thus the Emperor Frederick II. in 1213 and 1219 and Henry VII. in 1230 expressed their willingness to inflict the ban of the Empire upon any excommunicated offender who was still recalcitrant at the end of six weeks after his sentence. These conditions prevailed down to the Reformation; but in the countries where it prevailed a great change to place. The greater excommunication, as a secular punishment, was not recognized by the Reformed Church; the lesser was retained as a measure of instructive discipline, generally in the hands of the pastor, although Luther and others held that Scripturally it ought to be administered by the whole Christian community; but it was felt that if the pastor admitted an unworthy person to the Lord's Supper, he became partaker of the sin, and so the power of exclusion was left in his hands. The method of procedure prescribed by the German Reformers was public only for public sins, and always based on Matt. xviii. 55 sqq. Since the abolition of private confession did away with the warning of priest to penitent, it was made before church-members summoned for the purpose, preferably the elders, and followed by a prohibition to approach the communion-table and sometimes a withdrawal of other rites as well, including betrothal; but this was not necessarily public, unless the offender was obstinate, when he might be cut off from the Church in the presence of the whole congregation. The consistories always took part in the proceedings at one stage or another; and after the middle of the sixteenth century, as they had inherited many of the other episcopal powers, came to monopolize this, leaving the pastor only the duty of publishing the sentence. The greater excommunication practically died out in the seventeenth century, and the lesser fell very much into disuse with the growth of rationalism. It is, however, obvious that no religious community can hope to enforce its regulations which does not possess and if necessary use the power of excluding members who persistently refuse obedience to them. The modern Roman Catholic Church maintains the position taken in the canon law, in this as in other regards, though considerable modifications have taken place in practise, especially as a result of the constitution Apostlicę sedis of Pius IX. (1869), which removed a number of the cases of excommunication latæ sententiæ, while enforcing discipline vigorously in some other respects. See CHURCH DISCIPLINE.