OF THE VARIOUS KINDS OF LAW (SIX ARTICLES)
We must now consider the various kinds of law: under which head there are six points of inquiry:
(1) Whether there is an eternal law?
(2) Whether there is a natural law?
(3) Whether there is a human law?
(4) Whether there is a Divine law?
(5) Whether there is one Divine law, or several?
(6) Whether there is a law of sin?
Whether there is an eternal law?
Objection 1: It would seem that there is no eternal law. Because every law is imposed on someone. But there was not someone from eternity on whom a law could be imposed: since God alone was from eternity. Therefore no law is eternal.
Objection 2: Further, promulgation is essential to law. But promulgation could not be from eternity: because there was no one to whom it could be promulgated from eternity. Therefore no law can be eternal.
Objection 3: Further, a law implies order to an end. But nothing ordained to an end is eternal: for the last end alone is eternal. Therefore no law is eternal.
On the contrary, Augustine says (De Lib. Arb. i, 6): "That Law which is the Supreme Reason cannot be understood to be otherwise than unchangeable and eternal."
I answer that, As stated above (Q[90], A[1], ad 2; AA[3],4), a law is nothing else but a dictate of practical reason emanating from the ruler who governs a perfect community. Now it is evident, granted that the world is ruled by Divine Providence, as was stated in the FP, Q[22], AA[1],2, that the whole community of the universe is governed by Divine Reason. Wherefore the very Idea of the government of things in God the Ruler of the universe, has the nature of a law. And since the Divine Reason's conception of things is not subject to time but is eternal, according to Prov. 8:23, therefore it is that this kind of law must be called eternal.
Reply to Objection 1: Those things that are not in themselves, exist with God, inasmuch as they are foreknown and preordained by Him, according to Rom. 4:17 : "Who calls those things that are not, as those that are." Accordingly the eternal concept of the Divine law bears the character of an eternal law, in so far as it is ordained by God to the government of things foreknown by Him.
Reply to Objection 2: Promulgation is made by word of mouth or in writing; and in both ways the eternal law is promulgated: because both the Divine Word and the writing of the Book of Life are eternal. But the promulgation cannot be from eternity on the part of the creature that hears or reads.
Reply to Objection 3: The law implies order to the end actively, in so far as it directs certain things to the end; but not passively---that is to say, the law itself is not ordained to the end---except accidentally, in a governor whose end is extrinsic to him, and to which end his law must needs be ordained. But the end of the Divine government is God Himself, and His law is not distinct from Himself. Wherefore the eternal law is not ordained to another end.
Whether there is in us a natural law?
Objection 1: It would seem that there is no natural law in us. Because man is governed sufficiently by the eternal law: for Augustine says (De Lib. Arb. i) that "the eternal law is that by which it is right that all things should be most orderly." But nature does not abound in superfluities as neither does she fail in necessaries. Therefore no law is natural to man.
Objection 2: Further, by the law man is directed, in his acts, to the end, as stated above (Q[90], A[2]). But the directing of human acts to their end is not a function of nature, as is the case in irrational creatures, which act for an end solely by their natural appetite; whereas man acts for an end by his reason and will. Therefore no law is natural to man.
Objection 3: Further, the more a man is free, the less is he under the law. But man is freer than all the animals, on account of his free-will, with which he is endowed above all other animals. Since therefore other animals are not subject to a natural law, neither is man subject to a natural law.
On the contrary, A gloss on Rom. 2:14 : "When the Gentiles, who have not the law, do by nature those things that are of the law," comments as follows: "Although they have no written law, yet they have the natural law, whereby each one knows, and is conscious of, what is good and what is evil."
I answer that, As stated above (Q[90], A[1], ad 1), law, being a rule and measure, can be in a person in two ways: in one way, as in him that rules and measures; in another way, as in that which is ruled and measured, since a thing is ruled and measured, in so far as it partakes of the rule or measure. Wherefore, since all things subject to Divine providence are ruled and measured by the eternal law, as was stated above (A[1]); it is evident that all things partake somewhat of the eternal law, in so far as, namely, from its being imprinted on them, they derive their respective inclinations to their proper acts and ends. Now among all others, the rational creature is subject to Divine providence in the most excellent way, in so far as it partakes of a share of providence, by being provident both for itself and for others. Wherefore it has a share of the Eternal Reason, whereby it has a natural inclination to its proper act and end: and this participation of the eternal law in the rational creature is called the natural law. Hence the Psalmist after saying ( Ps. 4:6 ): "Offer up the sacrifice of justice," as though someone asked what the works of justice are, adds: "Many say, Who showeth us good things?" in answer to which question he says: "The light of Thy countenance, O Lord, is signed upon us": thus implying that the light of natural reason, whereby we discern what is good and what is evil, which is the function of the natural law, is nothing else than an imprint on us of the Divine light. It is therefore evident that the natural law is nothing else than the rational creature's participation of the eternal law.
Reply to Objection 1: This argument would hold, if the natural law were something different from the eternal law: whereas it is nothing but a participation thereof, as stated above.
Reply to Objection 2: Every act of reason and will in us is based on that which is according to nature, as stated above (Q[10], A[1]): for every act of reasoning is based on principles that are known naturally, and every act of appetite in respect of the means is derived from the natural appetite in respect of the last end. Accordingly the first direction of our acts to their end must needs be in virtue of the natural law.