These below excerpted from Wikipedia
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History
The Catholic Church claims that the penalty of excommunication is biblical and that both Paul of Tarsus and John the Apostle make reference to the practice of cutting people off from the community, in order to hasten their repentance. The Catholic Encyclopedia states that from the earliest days of Christianity, excommunication was the chief (if not the only) ecclesiastical penalty for laymen; for guilty clerics the first punishment was deposition from their office, i.e. reduction to the ranks of the laity. The Catholic Encyclopedia adds that during the first centuries of Christianity, excommunication was not regarded as a simple external measure, but also as one which touched the soul and the conscience. It was not merely the severing of the outward bond which holds individual to their place in the Church; it severed also the internal bond, and the sentence pronounced on earth was understood to be ratified in heaven.
During the Middle Ages, excommunication was analogous to the secular imperial ban or “outlawry” under common law. The individual was separated to some degree from the communion of the faithful. Formal acts of public excommunication were sometimes accompanied by a ceremony wherein a bell was tolled (as for the dead), the Book of the Gospels was closed, and a candle snuffed out—hence the idiom “to condemn with bell, book, and candle.”
Those under excommunication were to be shunned. Pope Gregory VII was the first to mitigate the proscription against communicating with an excommunicated person. At a council in Rome in 1079, he made exceptions for members of the immediate family, servants, and occasions of necessity or utility. In the mid-12th century, Pope Eugene III held a synod in order to deal with the large number of heretical groups. Mass excommunication was used as a convenient tool to squelch heretics who belonged to groups which professed beliefs radically different than those taught by the Catholic Church.
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Types of excommunication
The terminology used to qualify the modalities of excommunication may vary depending on the author.
The 1913 Catholic Encyclopedia distinguishes excommunication from the refusal of ecclesiastical communion, in which one bishop refuses to worship in common with another.
Anathema is a sort of aggravated excommunication, from which, however, it does not differ essentially, but simply in the matter of special solemnities and outward display.
A jure and ab homine
Excommunication is either a jure (by law) or ab homine (by judicial act of man, i.e. by a judge). The first is provided by the law itself, which declares that whosoever shall have been guilty of a definite crime will incur the penalty of excommunication. The second is inflicted by an ecclesiastical prelate, either when he issues a serious order under pain of excommunication or imposes this penalty by judicial sentence and after a criminal trial.
Latæ sententiæ and ferendæ sententiæ
Excommunication is either latæ sententiæ or ferendæ sententiæ.
Latae sententiae excommunication is incurred as soon as the offence is committed and by reason of the offence itself (eo ipso) without intervention of any ecclesiastical judge; it is recognized in the terms used by the legislator, for instance: “the culprit will be excommunicated at once, by the fact itself [statim, ipso facto]”.
Ferendae sententiae excommunication is considered by the law as a penalty and is inflicted on the culprit only by a judicial sentence; in other words, the delinquent is rather threatened than visited with the penalty, and incurs it only when the judge has summoned him before his tribunal, declared him guilty, and punished him according to the terms of the law. It is recognized when the law contains these or similar words: “under pain of excommunication”; “the culprit will be excommunicated”.
Public and occult
Excommunication ferendæ sententiæ can be public only, as it must be the object of a declaratory sentence pronounced by a judge; but excommunication latæ sententiæ may be either public or occult.
An excommunication is public through the publicity of the law when it is imposed and published by ecclesiastical authority; it is public through notoriety of fact when the offence that has incurred it is known to the majority in the locality, as in the case of those who have publicly done violence to clerics, or of the purchasers of church property. This excommunication is valid in the forum externum and consequently in the forum internum.
Excommunication is occult when the offence entailing it is known to no one or almost no one. This excommunication is valid in the forum internum only.
The practical difference of validities in the forums is very important:
He who has incurred occult excommunication should treat himself as excommunicated and be absolved as soon as possible, submitting to whatever conditions will be imposed upon him, but this only in the tribunal of conscience; he is not obliged to denounce himself to a judge nor to abstain from external acts connected with the exercise of jurisdiction, and he may ask absolution without making himself known either in confession or to the Sacred Penitentiaria. According to the teaching of Benedict XIV, “a sentence declaratory of the offence is always necessary in the forum externum, since in this tribunal no one is presumed to be excommunicated unless convicted of a crime that entails such a penalty”.
Public excommunication, on the other hand, is removed only by a public absolution; when it is question of simple publicity of fact (see above), the absolution, while not judicial, is nevertheless public, inasmuch as it is given to a known person and appears as an act of the forum externum.
In a case of occult excommunication the culprit has the right to judge himself and to be judged by his confessor according to the exact truth, whereas, in the forum externum the judge decides according to presumptions and proofs. Consequently, in the tribunal of conscience he who is reasonably persuaded of his innocence cannot be compelled to treat himself as excommunicated and to seek absolution; this conviction, however, must be prudently established.
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Latae sententiae
The 1983 Code of Canon Law attaches the penalty of latae sententiae (automatic) excommunication to the following actions:
- Apostates, heretics, and schismatics (can. 1364)
- Desecration of the Eucharist (can. 1367)
- A person who physically attacks the pope (can. 1370)
- A priest who in confession absolves a partner with whom they have violated the sixth commandment [offenses against chastity] (can. 977, can. 1384)
- A person who attempts to confer a holy order on a woman, and the woman who attempts to receive it (can. 1379)
- A bishop who consecrates another bishop without papal mandate (can. 1382)
- A priest who violates the seal of the confessional (can. 1388)
- A person who procures an abortion (can. 1398)
- Accomplices who were needed to commit an action that has an automatic excommunication penalty (can. 1329)
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Those who can excommunicate
Excommunication is either a jure (by law) or ab homine (by judicial act of man, i.e. by a judge). The first is provided by the law itself, which declares that whosoever shall have been guilty of a definite crime will incur the penalty of excommunication. The second is inflicted by an ecclesiastical prelate, either when he issues a serious order under pain of excommunication or imposes this penalty by judicial sentence and after a trial.
Excommunication is an act of ecclesiastical jurisdiction, the rules of which it follows. Hence the general principle: whoever has proper jurisdiction can excommunicate, but only his own subjects. Therefore, whether excommunications be a jure (by the law) or ab homine (under form of sentence or precept), they may come from the pope, from the bishop for his diocese; and from regular prelates for religious orders. But a parish priest cannot inflict this penalty. The subjects of these various authorities are those who come under their jurisdiction chiefly on account of domicile or quasi-domicile in their territory; then by reason of the offense committed while on such territory; and finally by reason of personal right, as in the case of regulars. As to excommunications ab homine, absolution from them is reserved by law to the ordinary who has imposed them.
Those who can be excommunicated
No one can be subject to ecclesiastical censure unless they be baptized, delinquent, and contumacious. Baptism confers initial jurisdiction, delinquency refers to having committed a wrong, and contumacious indicates the person’s willfull persistence in such conduct. Since excommunication is the forfeiture of the spiritual privileges of ecclesiastical society, all those, but those only, can be excommunicated who, by any right whatsoever, belong to this society. Consequently, excommunication can be inflicted only on baptized and living Catholics. It does not pertain to pagans, Muslims, Jews, and other non-Catholics.
No one is automatically excommunicated for any offense if, without any fault of his own, he was unaware that he was violating a law (1983 CIC 1323 n. 2) or that a penalty was attached to the law (1983 CIC 1324 §1 n. 9). The same applies if one was a minor, had the imperfect use of reason, was forced through grave or relatively grave fear, was forced through serious inconvenience, or in certain other circumstances (1983 CIC 1324).
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