I offer my apologies if I’ve posted in the incorrect subsection of the forums. Anyways, onto my question: what must one do to be automatically excommunicated for heresy? I know they must have the knowledge that they can be excommunicated for what they believe, but I’m a little foggy on memory about how much they believe the heresy, if they didn’t know that the Church taught something different, factors in.

For example, let’s say that it’s possible I may be automatically excommunicated from the grand church of chocolate for believing that tiramisu is a better flavor than German chocolate (don’t ask… :D). Let’s say also that for some odd reason the grand church of chocolate has the same rules about excommunication the Catholic Church has. If I was unaware of the fact that I have to believe German chocolate is better than tiramisu to stay in the grand church of chocolate, would I be excommunicated from them automatically?

Yeah, weird analogy, I know, but that’s the best I got, haha. Keep in mind the above is a ridiculous situation and I don’t believe that I’m going to be automatically excommunicated for heresy in real life. I’d just like a better understanding of it. Thank you!

So first, you are correct that a person must know that an act carries a latae sententiae (aka automatic) penalty. For the case of heresy one must continue in “obstinate denial or obstinate doubt” of things that must be believed. Obstinate in this case means that the person has been corrected on numerous occasions, so if they were unaware of Church teaching it would not be obstinate denial unless that denial continued after correction. This is where you get into the distinction of material vs formal heresy.

So the question is if a random person in the pew is automatically excommunicated for heresy? Highly unlikely. When we talked about heresy in class a few months ago, the instructor told us that unless someone is fairly vocal and holds some teaching authority they would not be counted as a heretic. As he put it, unless your bishop were to formally declare you a heretic after repeatedly correcting statements denying dogma, then you would not incur a latae sententiae excommunication. His take on it was that really only theologians and clergy who repeatedly and publically denied dogma would incur this penalty. Now perhaps some of our local canonists will correct me, but that is the read we got in class.

The usual provision that one must know about the law and its penalty for the penalty to apply does not encompass apostasy, heresy, or schism. Those three sins automatically excommunicate, regardless of canon law, because by the very nature of the offense the sinner is choosing to cut himself off from the Church.

To excommunicate the heresy or schism must be formal, not merely material. Apostasy is always formal and always excommunicates.

Formal heresy means that the person knows that a teaching is a required belief of the Catholic faith (i.e. to be believed with divine and catholic faith, not merely a non-infallible teaching), and yet obstinately denies or obstinately doubts that teaching. So formal heresy is never accidental (merely material), as when the person mistakenly thinks that the Church teaches one thing, rather than another.

That claim is completely false. The ordinary lay faithful can commit the grave sin of heresy; you don’t need have teaching authority, nor must you first be rebuked by a bishop. See canon law on this point. There is no limitation of the law to only teachers or only those first rebuked by a bishop.

Thanks, Ron. That was actually the take of many of us in the class. This is very likely the difference in Canon law and the view from a theologian’s standpoint (the instructor is a SThD in systematic theology). I beleive his point is that it would a theologian, clergy or someone else involved in teaching that would most likely be in a position of a formal heretic. His reasoning was that the average man in the pew is not repeatedly engaged in being corrected about denial of dogmatic elements of the faith. When someone brought up Catholics that reject birth control he said that since this is doctrine, not dogma, that it does not raise to the level of heresy.

I completely agree that a layman can be a formal heretic, but it must be understood that heresy is not simply disagreeing with a Church teaching.

Just to be clear:
A person can profess or believe something that is heretical.
That does not necessarily make them a heretic.

A person must be a Catholic to be a heretic.
For instance, “Heretic” does not apply to current protestants who are born into their faith, who have beliefs that might be heretical.

This is important so that we do not incorrectly use inflammatory legal language that does not apply to a person.

Church teaching against contraception falls under the infallibility of the ordinary and universal Magisterium, and such teaches of the OUM are to be believed with divine and catholic faith. So, any Catholic who rejects Church teaching on contraception is guilty of at least material heresy.

Again, it is not necessary to the definition of the sin of formal heresy that a person first be corrected repeatedly about a denial of dogma. This point is absolutely clear from Church teaching that a person might be guilty of occult heresy, of a heresy hidden in the heart and mind.

Who is this instructor?

If a baptized Christian – any Christian – believes an heretical idea, then that is at least material heresy. Canon law is very clear that all baptized Christians are, in principle, under the authority of the Church. I would say that a person is only a heretic if they commit formal heresy. But Protestants are in a state of material heresy.

It is possible, but probably very uncommon, for a Protestant to realize that the Catholic Faith is the true faith, but then refuse to convert due to the loss of a teaching or leadership position that would ensue, or because family and friends would object. So a Protestant could possibly be a formal heretic. But generally, it is mere material heresy.

The sins of apostasy, heresy, and schism automatically excommunicate regardless of church law. So this is fundamentally a matter of morality, and only secondarily a matter of canon law.

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