I was just hoping that some of you could help me with a question I have. I was in a "Catholic" chat room and a Catholic there told me that lay Catholics cannot judge protestants as being heretics because no Catholic can ever know for certain if that protestant has committed the mortal sin of heresy because no Catholic can know if that protestant has met the 3 requirements for Mortal Sin to occur.
Those 3 are grievous matter, sufficient reflection and full consent of the will. That Catholic told me that even if a protestant publicly promulgates heresy, then we can't judge them and call them a formal heretic. In fact he apparently judged me and said I'm not a Catholic for calling protestants heretics. So I guess to him, I'm not a Catholic, but the protestants are Catholic. Anyway, what say all of you?

I was just hoping that some of you could help me with a question I have. I was in a "Catholic" chat room and a Catholic there told me that lay Catholics cannot judge protestants as being heretics because no Catholic can ever know for certain if that protestant has committed the mortal sin of heresy because no Catholic can know if that protestant has met the 3 requirements for Mortal Sin to occur.
Those 3 are grievous matter, sufficient reflection and full consent of the will. That Catholic told me that even if a protestant publicly promulgates heresy, then we can't judge them and call them a formal heretic. In fact he apparently judged me and said I'm not a Catholic for calling protestants heretics. So I guess to him, I'm not a Catholic, but the protestants are Catholic. Anyway, what say all of you?

A Catholic who rejects the faith, or any part of the faith, is a formal heretic

A Protestant who sincerely does not understand that Christ founded the Catholic Church is a material heretic.

Objectively Protestants are heretics in that they believe heresy.

But sin involved if any, does not change the objective fact.  

Some Protestants reject Catholicism because they would not be able to use contraception.  They are culpable for not being Catholic and their sin is worse than the Protestant who truly does not know better.

Some are really brainwashed from their youth that Catholics are members of a Church that is the Whore of Babylon.  They are not as culpable.

Those with a keen sense of history and of the teaching of the Apostles, Fathers and Doctors do not have an excuse to deny the plausibility of Catholicism outright.  

Believing heresy makes one a heretic in a certain sense.  But I believe, technical one must have the faith and then reject it to be a formal heretic.  Protestants, to be charitable, assuming they do not know better are material heretics.

Their culpability (sinfulness because of that belief) is subjective.  It depends upon their culpability.  Are they willfully blind or sincere or some mixture.

The only criterion by which we can know whether a Protestant who denies a dogma of the Catholic Church holds erroneous opinions in good faith or whether he is now a heretic completely bereft of the supernatural virtue of faith, is how he responds to the preaching of the true Faith. If upon hearing it, he immediately converts or considers converting, he probably was in good faith. If he does not, he probably was not.

It is a question not of much practical importance anyway, since it would be a sin of presumption for one not to make use of all the available means of salvation, or to encourage others to do so. Whether or not Protestants are in good faith, we would still sin if we told them just to "remain as they are", as some unfortunately propose today.

This is clearly taught by both the Catechism of St.Pius X and Baltimore, the latter of which specifically addresses the question with regard to Protestants. Suffice to say in practice that traditionally Protestants who live among Catholics and would have had the opportunity to be reconciled to the Church are never presumed to be invincibly ignorant as such, but must rather be visibly brought back to the sole ark of salvation.

http://sedevacantist.com/essayonheresy.htm

http://sedevacantist.com/pertinacity.html

Application of these Terms to Heresy

With regard to the sin of heresy, it was said that the matter was the intellectual error involved in assenting to a heterodox proposition, while the form was the obstinate attachment of the will. And once again this distinction usefully clarified the fact that one who assents to a heterodox proposition by inadvertence, without obstinate attachment of the will, was not guilty of the sin of heresy.

What muddied the waters was the misleading linguistic development by which material heresy was said to make the person professing it a material heretic. No conclusion could seem more natural to the layman, but it does not in fact follow in logic. A retired lion-trainer is not, after all, a man who trains retired lions! And a serious problem arises when one designates as a material heretic anyone who assents, without moral guilt, to a heretical proposition. The first is that you have created a category which comprises two quite distinct sorts of member and you therefore run the risk of confusing the two. For according to that definition, a good Catholic who inadvertently holds a condemned doctrine, not realising that it is condemned is a material heretic. And so too is a Protestant if he is invincibly ignorant of the Church's status. And while it is true that there is a resemblance between the two cases (for both indeed hold in their minds unorthodox doctrine and neither is culpable in the eyes of God for doing so), nevertheless there is also a huge gulf between them. For the former is a Catholic, habitually adhering to the Catholic rule of faith, whereas the latter is a non-Catholic, with no knowledge of the correct rule of faith and tossed about on the treacherous sea of private opinion.

The inevitable consequence of this misleading assimilation of two such different sorts of person is that they will gradually come to be considered truly alike. This could happen in either of two ways. Mistaken Catholics could be regarded as no better than Protestants in good faith (and some “hard-liners” have practically taken this view, arguing that the most innocent error creates a presumption of heretical animus - a notion we have already seen to be false). More common has been the no less calamitous view that a Protestant, if invincibly ignorant of the status of the Church, is no worse off than a Catholic who inadvertently makes an incorrect doctrinal statement - as though adherence to the Catholic rule of faith, i.e. submission to the Magisterium, were irrelevant, whereas in fact it is what juridical membership of the Church depends on.

Correctly, the material element involved in being a heretic is conscious dissent from the Catholic rule of faith, while the formal element is the perverse state of the will which this entails. The distinction thus made, a Catholic who inculpably advances a heretical proposition by inadvertence may perhaps be said to have advanced a material heresy; but he cannot be called a material heretic. He is not a heretic in any sense. A heretic is one who dissents altogether from the Catholic rule of faith, and he will be called a material heretic if he is invincibly ignorant of the authority of the Church which he rejects, and a formal heretic if the Church's authority has been sufficiently proposed to him, so that his dissent from it is culpable. (This is clearly explained by Cardinal Billot: De Ecclesia Christi, ed. 4, pp. 289-290)


So according to the correct usage of the term, as outlined above, a Catholic can never become a material heretic. He is not invincibly ignorant of the Church's authority, and any conscious dissent from her teachings will therefore make him a formal heretic. Material heretics are exclusively those baptised non-Catholics who err in good faith. That is why Dr Ludwig Ott notes that “public heretics, even those who err in good faith (material heretics), do not belong to the body of the Church, that is to the legal commonwealth of the Church. (Fundamentals of Catholic Dogma, p.311)

And in fact Dr Ott's preferred expression - “heretics who err in good faith” is the one used in the Code of Canon Law (Canon 731), which completely eschews the potentially misleading term “material heretics”

http://sedevacantist.com/judgeheresy.html

This last one kind of speaks as to why SVs should not judge the recognize and resisters to be heretics as the reason why they feel forced to acknowledge public heretics as the head of their Church is because they want to submit to the Church as all good Catholics must.  It is because of their belief in the papacy that they feel they must accept him despite everything that makes their shepherd look like a wolf.  To that extant it is commendable that they defend the one they believe to be the Pope.  Of course the "R and Rs" should not judge the SVs to be heretics either for defending the papacy against heretical/non-Catholic claimants.  

http://sedevacantist.com/heresyhistory.html