306. The Natural Law is of universal obligation. It is in force in all places, at all times, and for all persons. (a) Thus, those who have not the use of reason, such as infants and the insane, are subject to the Natural Law on account of their human nature which is injured by any transgression of its inclinations. Their ignorance, of course, excuses them from formal sin (see 24 sqq., 97 sqq.). Example: It is sinful to induce or permit children to blaspheme or become intoxicated, not only because of scandal or of harm done to them, but also because such things are necessarily repugnant to their dignity as human beings. (b) those who have the use of reason are subject to the Natural Law, and their transgressions are imputable as formal sins and incur the debt of punishment.
307. The Natural Law is unchangeable, not as regards additions, but as regards subtractions. (a) Additions may be made to the Natural Law, for, in many points not determined by it, it is well that supplementary regulations be made to provide for particular situations. These additions, made by Positive Law, divine and human, are amplifications rather than changes, for they must not be out of harmony with Natural Law. (b) Subtractions may not be made from the Natural Law—that is, there can be no exception when it declares that a certain thing must always be observed, and there can be no abrogation when it declares that a certain thing must be observed usually.
308. From the foregoing it follows that no precept of the Natural Law can be abrogated—that is, repealed and deprived of all force, so that what was today a precept of nature should no longer be such tomorrow; for the necessities of nature on which the Natural Law is based do not change.
309. As to the question whether any precepts of the Natural Law may be dispensed or not, distinction must be made between two kinds of dispensation.
(a) A dispensation in the strict sense is granted when a legislator relaxes for a particular case the obligation of a law, although the subject-matter of the law still remains. Example: Titus is in the class of those who are bound by the law of fast, but he is exempted by competent authority from the obligation of the law.
(b) A dispensation in the wide sense is granted when the subject-matter of the law is taken away by the legislator himself or by another, so that it ceases to be comprehended under the law, although the obligation of the law still remains. Example: Balbus owed money to Caius, but, as Caius forgave him the debt, he is no longer in the class of those who are bound by law as debtors to Caius; he is not exempted, however, from the obligation of the general law that one must pay one’s debts.
310. There are various opinions as to the possibility of a dispensation from the Natural Law granted by God, but the following doctrine seems the most probable.
(a) God Himself cannot dispense in any way from those precepts whose matter is necessary (see 302), such as axiomatic precepts (viz., those that prohibit malice and those that command duties to be fulfilled at a proper time and place). For all the subject-matter of these precepts is intrinsically either consonant with or dissonant from right reason. Example: God could not by decree abolish the Ten Commandments, for, as long as God is God, He must remain worthy of worship, praise and love; and, as long as man is man, it must be against his rational nature to murder, steal, lie. etc.
(b) God cannot grant a dispensation in the strict sense from those precepts of the Natural Law whose matter is contingent, such as the precepts against the taking of human life, against taking possessions from others against their will, etc. For, as long as the subject-matter of these precepts remains what it is supposed to be by the law, transgression of them is necessarily opposed to reason. Example: God cannot command the killing of a person who has the right to life, nor the taking of property that rightly belongs to another.
(c) God can grant a dispensation in the wide sense from contingent precepts of the Natural Law—that is, He can make a change as regards the subject-matter, so that it no longer falls under the law. Thus, since God is the supreme Lord of life and property, He can without injury to human rights command that a person be put to death or deprived of his property by another. These acts would not constitute murder (i.e., unjust homicide) or stealing (i.e., unlawful taking); for God has a higher claim on life and possessions than the immediate owners have. Examples: The command to Abraham to kill his son was not a dispensation from the law against murder any more than the sending of death to the first-born of Egypt was the commission of murder by God. The command given the Israelites to carry away with them the goods of the Egyptians was not a dispensation from the law against theft, any more than the destruction of the fruits of the Egyptians by plagues was the commission of theft by God.