Quite a bit if you ask me.
A reader writes:
What does excommunication do? What is the definition of excommunication? What is its purpose? How has it changed in the new law versus the old law?
Let’s start with the first question: what excommunication does. Here is what the Code of Canon Law says it does:
Canon 1331
§1. An excommunicated person is forbidden:
1° to have any ministerial participation in celebrating the sacrifice of the Eucharist or any other ceremonies of worship whatsoever;
2° to celebrate the sacraments or sacramentals and to receive the sacraments;
3° to exercise any ecclesiastical offices, ministries, or functions whatsoever or to place acts of governance.
§2. If the excommunication has been imposed or declared, the offender:
1° who wishes to act against the prescript of §1, n. 1 must be prevented from doing so, or the liturgical action must be stopped unless a grave cause precludes this;
2° invalidly places acts of governance which are illicit according to the norm of §1, n. 3;
3° is forbidden to benefit from privileges previously granted;
4° cannot acquire validly a dignity, office, or other function in the Church;
5° does not appropriate the benefits of a dignity, office, any function, or pension, which the offender has in the Church.
If you read the above, you will see that most of the effects of excommunication will affect clerics rather than laypeople. For the average layperson, the principal effects are that he cannot receive the sacraments or perform any ecclesiastical ministries or functions (e.g., being an extraordinary minister or lector).
Now for the second question: how excommunication is defined. The current Code does not offer a definition, however the 1917 Code of Canon Law does:
Canon 2257
§1. Excommunication is a censure by which one is excluded from the communion of the faithful with the effects that are enumerated in the canons that follow and that cannot be separated.
The problem with this definition–which raises the subject of the fourth question (how the new law differs from the old)–is that there are elements of it that obviously do not apply in the new law. The most prominent of these is the idea of exclusion from the communion of the faithful (i.e., ecclesiastical communion rather than Eucharistic Communion). This is simply not one of the censure’s effects under current law. If I were to propose a contemporary definition, it would probably be something like: “Excommunication is a medicinal penalty which has the effects ennumerated in Canon 1331 of the Code of Canon Law.”
You’ll notice that I just referred to excommunication as a “medicinal penalty.” This brings up the third question (what excommunication is for). A medicinal penalty, also known as a censure, is a penalty intended to bring about repentance on the part of an offender so that he may be fully reconciled with God and the Church. Canon Can. 1312 §1, 1° notes that “medicinal penalties, or censures . . . are listed in cann. 1331-1333.” Since excommunication is listed in 1331, it’s one of those.
On the fourth question, there is much more that can be said. The current law on excommunication differs markedly from the former law (including, for example, a dramatic reduction in the number of offenses that may result in excommunication). Unfortunately, blog entries have limited space, so I hope this will suffice for now.
Yes, it does suffice. Thank you very much.