Section — Wouters, Manual of Moral Theology
Scholion. On the Propagation of Faith
I. Christ the Lord entrusted the deposit of faith to the Church, so that she herself, with the Holy Spirit continually assisting, might guard revealed doctrine holily and expound it faithfully (can. 1322, § 1). This is clear from Sacred Scripture.2
II. The Church, independently of any civil power, has the right and duty of teaching the evangelical doctrine to all nations (can. 1322, § 2). This likewise is taught by Sacred Scripture.3
III. As regards the persons upon whom the aforesaid right and duty rests, the Code teaches: The office of preaching the Catholic faith is committed chiefly to the Roman Pontiff for the universal Church, and to Bishops for their dioceses (can. 1327, § 1). Bishops, however, are bound by the duty of preaching the Gospel personally by themselves, unless they are prevented by a legitimate impediment; and besides, in addition to parish priests, they must also take other suitable men as helpers for carrying out this office of preaching salutarily (can. 1327, § 2). But to those who are not taken up by legitimate authority, public preaching is forbidden, according to these words of the Code: No one may exercise the ministry of preaching unless he has received a mission from a legitimate Superior, by a faculty particularly given, or by an office conferred, to which by the sacred canons the office of preaching is attached (can. 1328). I said public preaching; for private preaching belongs to all. Yet disputation properly so called is prohibited, for example, to those for whom it would be dangerous; sometimes it is prescribed, for instance if someone were equal to that duty and the honor of God or the salvation of neighbor required it. Yet can. 1325, § 3 must be attended to: "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 is urgent, of the local Ordinary."
IV. As regards preaching to non-Catholics specifically, note:
Local Ordinaries and parish priests should have non-Catholics dwelling in their dioceses and parishes commended to themselves in the Lord (can. 1350, § 1).
In other territories the entire care of missions among non-Catholics is reserved uniquely to the Apostolic See (can. 1350, § 2); and the Holy See exercises that care especially through the Sacred Congregation de Propaganda Fide, and, if Easterners are in question, through the Sacred Congregation for Orientals. But so that the said Congregations may be able to attain the end:
a) Religious institutes to which some mission has been entrusted should provide for it according to their strength.
b) Bishops, parish priests, and others, when opportunity is given, should foster an apostolic spirit in young men. "And you," thus Benedict XV in the Encyclical Maximum illud4 addresses the Bishops, "will do a thing especially worthy of your love of religion, if both in the clergy and in the diocesan Seminary you carefully foster the seeds of apostleship which someone perhaps has shown to be present in himself. Nor should any appearance of right deceive you, or any human reason move you, as if what you have permitted to foreign Missions you seem to have detracted from the usefulness of your diocese. For in place of one whom you send away abroad, God will raise up for you at home several very useful priests."
c) Let all assist missionaries: 1. by prayers, "which prayers, if ever at other times, certainly cannot lack effect in this cause, than which none is more excellent, none more pleasing to God";5 2. by alms.6
Whether some priest in particular, on account of the spiritual necessity of nations, must come to their aid, see in the treatise on the cultivation of charity.
Question. To what extent can some authority compel unbelievers to hear or embrace the faith?
Response 1. The Church cannot compel unbelievers to hear the faith, since she lacks jurisdiction over them; the temporal prince of unbelievers can do this.
Response 2. No authority can directly compel unbelievers to embrace the faith, even sufficiently proposed, since conversion is a matter of persuasion and will, not of coercion (St. Thomas, II-II, q. 12, a. 1, ad 3). Yet they can be compelled indirectly, for example by hope of a good not owed or fear of an evil otherwise owed. Besides, the secular prince can compel unbelievers to bid farewell to errors and rites opposed to natural law; indeed the prince cannot tolerate the said errors and rites except on account of a most grave cause7 (St. Thomas, II-II, q. 10, a. 11; St. Alphonsus, II, 18).
Response 3. The Church per se can compel heretics and apostates to return, and this by penalties both spiritual and temporal (St. Thomas, II-II, q. 10, a. 8); this power of compelling heretics and apostates, according to the determination of the Church, can also belong to secular princes, as protectors of the Church, and must be exercised by them insofar as the Church prescribes it.
1 Cf. Aertnys-Damen, II, n. 315 bis.
2 Matt. 28:19-20; John 14:16, 17, 26.
4 November 30, 1919 (Acta Apostolicae Sedis 1919, p. 452).
5 Benedict XV, in the cited Encyclical.
6 Benedict XV, in the cited Encyclical.
7 Leo XIII, Encyclical Immortale Dei, November 1, 1885; Encyclical Libertas, June 20, 1888.