§ II. On Heresy

Heresy is error against some truth of faith proposed by the Church, in one who received the faith through baptism. But it is: 1st. formal, which is heresy properly so called, and is had when the error is voluntary and pertinacious, or material, by which someone ignorantly adheres to error; 2nd. purely internal, or purely external, or manifested, according as it is had only internally or externally, or in both ways; 3rd. occult or notorious, according as it is known to no one or to only a few, or to many.

To heresy is referred apostasy, which is total defection from the Christian faith.

I Say. Formal heresy is always a most grave sin, but material heresy is free from every fault. The reason for the first is both because heresy is opposed to one of the chief virtues, namely faith, and because heresy tends directly and immediately to contemning God. The reason for the second is that a material heretic, as is supposed, errs from invincible ignorance.

Question. What are the signs of material and formal heresy?

Response. He is to be judged a material heretic only: 1st. who is prepared to submit himself to the judgment of the Church as soon as he shall have known it; 2nd. who, born among heretics, has known nothing concerning the true faith and has never doubted concerning his own religion; 3rd. who, doubting, has studied to know the truth as much as he could, and has not yet arrived at it. - But he will be reputed a formal heretic: 1st. who doubts, and from pertinacity does not wish to inquire further; 2nd. who again from pertinacity maliciously turns his intellect away from the motives of truth, so that he may adhere to his own sect; 3rd. who, having acknowledged the truth, still contradicts the Church.

Canon 1325, § 2, most clearly indicates who is and is to be judged a heretic, who an apostate, who a schismatic:

§ 2. After baptism has been received, if anyone, while retaining the Christian name, pertinaciously denies some truth from among those to be believed by divine and Catholic faith, or doubts concerning it, he is a heretic; if he totally withdraws from the Christian faith, he is an apostate; finally, if he refuses to be subject to the Supreme Pontiff or refuses to communicate with the members of the Church subject to him, he is a schismatic (Can. 1325).

Those who submit themselves to Christian Science for being healed sin gravely, because they formally participate in that damnable superstition, whose characteristic and special act is to heal. As is evident, he would deny the faith who gave his name to such a superstition.¹

It is not enough to avoid heretical depravity, but it is also necessary diligently to flee those errors which approach it more or less; wherefore all must also observe the constitutions and decrees by which evil opinions of this kind have been proscribed and prohibited by the Holy See (Can. 1324).

On the Care of Non-Catholics:

§ 1. Let local Ordinaries and pastors hold as commended to themselves in the Lord the non-Catholics dwelling in their dioceses and parishes.

§ 2. In other territories the whole care of missions among non-Catholics is reserved solely to the Apostolic See (Can. 1350).

Let no one be compelled unwillingly to embrace the Catholic faith (Can. 1351).

With relation to discussions, especially public ones, can. 1325, § 3 establishes thus:

§ 3. Let Catholics beware lest they have disputations or conferences, especially public ones, with non-Catholics, without permission of the Holy See or, if the case presses, of the local Ordinary.

¹ Cf. Addenda, p. 1094, n. 28.