Please provide theological support for this view.
Billot suggests that those who do not recognize the authority of the Church and choose another rule for their guide (that would be non-Catholics, not Catholics, correct?) are material heretics. Catholics can be in error, but they are not material heretics:
"Now, heretics are divided into formal and material. Formal heretics are those to whom the authority of the Church is sufficiently known; material, those who labor under invincible ignorance concerning the Church herself, and choose in good faith another rule for their guide. Heresy therefore is not imputed to material heretics as sin, nor, furthermore, is there necessarily a lack of that supernatural faith which is the beginning and root of all justification. For perhaps they explicitly believe the principal articles, and believe the rest not explicitly but implicitly, by the disposition of mind and the good will of adhering to all those things which would be sufficiently proposed to them as revealed by God. Furthermore, they can still belong in voto to the body of the Church, and have the other conditions required for salvation. Nevertheless, so far as pertains to the real incorporation in the visible Church of Christ presently being treated, the thesis places no distinction between formal or material heretics, understanding everything according to the notion of material heresy just explained, which is also the only proper and genuine notion. For if by a material heretic you meant one who, professing that in matters of faith he depends on the Magisterium of the Church, but still denies something defined by the Church which he does not know has been defined, or holds an opinion opposed to Catholic doctrine for the reason that he thinks that it is taught by the Church, it would in this case be absurd to posit that material heretics are outside the body of the true Church, and in addition, in this way, the legitimate meaning of the word would be completely overturned. For only then is it said that there is material sin, when the things that belong to the definition of such a sin are materially posited, but excluding reflection or deliberate volition. Now, what pertains to the definition of heresy is the departure from the rule of the ecclesiastical Magisterium, which in this case is not present, because it is a simple error of fact concerning that which the rule dictates. And therefore, there can be no place even materially for heresy. (Louis Card. Billot, Tractatus de Ecclesia Christi (Romae, 1927), v. 1, p. 296-29"
This is actually a great quote. Not that Billot's position is correct, but because this can be spun off into a lot of great theological threads, especially regarding the soteriological and ecclesiological issues. Thanks for sharing it.
Billot isn't saying that Catholics cannot be material heretics. He's claiming that both can be material heretics ... but in different senses.
Here's the part where he talks about how CATHOLICS can be material heretics, and this is exactly what I have been arguing against Lastdays here:
For if by a material heretic you meant one who, professing that in matters of faith he depends on the Magisterium of the Church, but still denies something defined by the Church which he does not know has been defined, or holds an opinion opposed to Catholic doctrine for the reason that he thinks that it is taught by the Church, it would in this case be absurd to posit that material heretics are outside the body of the true Church
But Billot falsely applies the formal-material distinction of MORAL theology to the faith in an attempt to get Prots and other heretics inside the Church.
When it comes to the faith, the matter of the faith are the propositions believed, and the form of the faith is accepting the Magisterium as the formal rule of faith. So Billot correctly identifies these when he says "professing that in matters of faith he depends on the Magisterium" (form) but "still denies something defined by the Church" (matter). Billot clearly says that in the case of Catholics who are material heretics "it would be absurd to posit that material heretics [i.e. Catholic material heretics] are outside the body of the true Church." This is precisely what I have been telling Lastdays.
Let's say it were possible that I accepted every single truth taught by the Church but still did not believe them on the authority of the Church ... I do NOT have supernatural faith, because I do not have the supernatural formal motive of faith. Conversely, that's why those who pertinaciously reject anything taught by the Church are said to be heretics ... because they thereby reject the rule of faith (Church teaches it but I don't believe it anyway). That's the reason for the saying that if you reject one dogma, you reject them all. By rejecting one you reject the AUTHORITY behind ALL of them and then end up believing the ones you still happen to accept based on your own authority rather than the authority of the Church.
As for Billot's allegation that "good will" can supply for the form (dependence on the Magisterium as their authority), I'd rather not get into that can of worms because there you can see the theological trends that will ultimately lead to Vatican II ecclesiology. This is the whole Father Feeney question. I'll probably spin this Billot quote off into another thread there. In any case, Billot is confounding the formal-material of moral theology [sinful intenion (form) vs. the act itself (matter)] with the form and matter of possessing supernatural faith. These are two different things altogether and Billot is mixing them up in order to get Prots into the Church. You can have the best intentions in the world, but you do not have the faith if you do not have a supernatural motive of faith. That's just Pelagian crap, and it's the cause of all the Vatican II theological errors.