(c) The Church can make laws in matters that were left free by our Lord whenever this will promote the better observance of His law (e.g., many church laws for the clergy and religious, for the conduct of worship, for administration, etc.).
426. The acts that may be commanded by the Church are of various kinds.
(a) The Church may command acts that are purely external (e.g., fasting) and acts that are partly external and partly internal, that is, those external acts to which, from the nature of things or from law, a special moral act of the intellect or will must be joined (e.g., a true oath, a worthy confession or Communion).
(b) The Church may command acts that are purely internal, that is, acts of the intellect or will that are not necessarily connected with any external act (such as meditation, the intention in applying Mass, ctc.), whenever she is explaining, applying, or determining the Divine Law, or acting in virtue of the power of Christ. Examples: The Pope may define a dogma to be accepted internally. A confessor may impose as penance a pious meditation. The Church prescribes the days when pastors must intend to offer Mass for their people. A religious superior may command a spiritual retreat.
(c) It is more probable that, apart from instances such as those just given, the Church cannot legislate regarding acts that are purely internal. For unlike the divine Legislator, who sees the internal acts of the soul and who can pass judgment on them, the Church cannot read the heart or judge the conscience. Hence, it would appear useless for the Church to give commandments about acts that elude her knowledge, all the more so since the Divine Law has given commands and prohibitions regarding internal acts and no one can escape the judgment of God.
427. Those Bound by General Laws.—The general laws of the Church oblige all and only such persons as are at once subjects of the Church and capable of receiving a law (Canon 12).
(a) By Baptism one becomes a member of the Church, and hence it is the baptized who are subject to ecclesiastical laws; (b) by her laws, the Church commands only human and deliberate acts or omissions, and hence it is only those who can reason that are subject to those laws. (c) Moreover, unless the law expressly rules otherwise, those who, although they have attained the use of reason, have not yet completed their seventh year are not bound by purely ecclesiastical law. Specific exceptions are stated in the law. Thus: (1) Canons 854, Sec.2, and 940, Sec.1, regarding the reception of the sacraments in danger of death, Canon 859, Sec.1, stating the precepts of Easter Communion, and Canon 906, containing the precepts of annual confession, declare that the law in these matters is binding on persons having the use of reason, regardless of the actual completion of the seventh year, The law of fasting in Canon 1254, Sec.2 binds after the completion of the twenty-first year. (2) Canon 1099 explicitly exempts non-Catholics, in their own marriages, from the ecclesiastical form of marriage; also Canon 1070 exempts them from the impediment of disparity of cult. (3) The habitually insane are considered as infants under seven (Canon 88, Sec.3). Accordingly, although they are bound by the Divine Law during lucid moments, they are not usually bound by purely ecclesiastical laws during this period.
428. By the unbaptized are here understood, not only those who have never received Baptism (such as infidels, pagans, Mohammedans, Jews, catechumens), but also those who were baptized invalidly. The divine law of receiving Baptism and entering the Church applies to these persons, but, as long as they are unbaptized, they are not subjects of the Church. Thus: (a) directly they are not obliged by any ecclesiastical law, and hence it is not sinful in itself to ask them to do what is forbidden by such laws (e.g., work on a holyday); (b) indirectly they become subject to ecclesiastical law when they enter into law-governed relations with the baptized who are subject to church law. Example: An unbaptized person who marries a Catholic is married invalidly, unless the law on dispensation has been observed.
429. Baptized non-Catholics include heretics and schismatics. Thus: (a) objectively, these persons are obliged by ecclesiastical laws, unless they are excepted by the law itself, and hence it is not lawful directly to induce them to transgress a Church law (e.g., to eat meat on Friday); (b) subjectively, they are generally excused from formal sin in the non-observance of Church laws, and it is not a sin to co-operate materially in such non-observance (e.g., by giving meat on Friday to a Protestant in good faith who requests it or wishes it).
430. It is held that the Church is more lenient as regards those baptized as non-Catholics, that is, those who were born and brought up in some non-Catholic sect. Thus: (a) laws that have for their object the sanctification of the individual (such as fasting and abstinence, Sunday Mass, etc.), are not insisted on for them, since this would hurt rather than help their spiritual interests; (b) laws that have for their object the protection of the public welfare (such as the laws regarding mixed marriage), apply also to baptized non-Catholics.