Whether the moral precepts of the Law are about all the acts of virtue?
Objection 1: It would seem that the moral precepts of the Law are not about all the acts of virtue. For observance of the precepts of the Old Law is called justification, according to Ps. 118:8: "I will keep Thy justifications." But justification is the execution of justice. Therefore the moral precepts are only about acts of justice.
Objection 2: Further, that which comes under a precept has the character of a duty. But the character of duty belongs to justice alone and to none of the other virtues, for the proper act of justice consists in rendering to each one his due. Therefore the precepts of the moral law are not about the acts of the other virtues, but only about the acts of justice.
Objection 3: Further, every law is made for the common good, as Isidore says (Etym. v, 21). But of all the virtues justice alone regards the common good, as the Philosopher says (Ethic. v, 1). Therefore the moral precepts are only about the acts of justice.
On the contrary, Ambrose says (De Paradiso viii) that "a sin is a transgression of the Divine law, and a disobedience to the commandments of heaven." But there are sins contrary to all the acts of virtue. Therefore it belongs to Divine law to direct all the acts of virtue.
I answer that, Since the precepts of the Law are ordained to the common good, as stated above (Q 90, A 2), the precepts of the Law must needs be diversified according to the various kinds of community: hence the Philosopher (Polit. iv, 1) teaches that the laws which are made in a state which is ruled by a king must be different from the laws of a state which is ruled by the people, or by a few powerful men in the state. Now human law is ordained for one kind of community, and the Divine law for another kind. Because human law is ordained for the civil community, implying mutual duties of man and his fellows: and men are ordained to one another by outward acts, whereby men live in communion with one another. This life in common of man with man pertains to justice, whose proper function consists in directing the human community. Wherefore human law makes precepts only about acts of justice; and if it commands acts of other virtues, this is only in so far as they assume the nature of justice, as the Philosopher explains (Ethic. v, 1).
But the community for which the Divine law is ordained, is that of men in relation to God, either in this life or in the life to come. And therefore the Divine law proposes precepts about all those matters whereby men are well ordered in their relations to God. Now man is united to God by his reason or mind, in which is God's image. Wherefore the Divine law proposes precepts about all those matters whereby human reason is well ordered. But this is effected by the acts of all the virtues: since the intellectual virtues set in good order the acts of the reason in themselves: while the moral virtues set in good order the acts of the reason in reference to the interior passions and exterior actions. It is therefore evident that the Divine law fittingly proposes precepts about the acts of all the virtues: yet so that certain matters, without which the order of virtue, which is the order of reason, cannot even exist, come under an obligation of precept; while other matters, which pertain to the well-being of perfect virtue, come under an admonition of counsel.
Reply to Objection 1: The fulfilment of the commandments of the Law, even of those which are about the acts of the other virtues, has the character of justification, inasmuch as it is just that man should obey God: or again, inasmuch as it is just that all that belongs to man should be subject to reason.
Reply to Objection 2: Justice properly so called regards the duty of one man to another: but all the other virtues regard the duty of the lower powers to reason. It is in relation to this latter duty that the Philosopher speaks (Ethic. v, 11) of a kind of metaphorical justice.
The Reply to the Third Objection is clear from what has been said about the different kinds of community.
I–II · Q. 100, Art. 3: Whether all the moral precepts of the Old Law are reducible to the ten precepts of the decalogue?
Whether all the moral precepts of the Old Law are reducible to the ten precepts of the decalogue?
Objection 1: It would seem that not all the moral precepts of the Old Law are reducible to the ten precepts of the decalogue. For the first and principal precepts of the Law are, "Thou shalt love the Lord thy God," and "Thou shalt love thy neighbor," as stated in Mat. 22:37,39. But these two are not contained in the precepts of the decalogue. Therefore not all the moral precepts are contained in the precepts of the decalogue.
Objection 2: Further, the moral precepts are not reducible to the ceremonial precepts, but rather vice versa. But among the precepts of the decalogue, one is ceremonial, viz. "Remember that thou keep holy the Sabbath-day." Therefore the moral precepts are not reducible to all the precepts of the decalogue.
Objection 3: Further, the moral precepts are about all the acts of virtue. But among the precepts of the decalogue are only such as regard acts of justice; as may be seen by going through them all. Therefore the precepts of the decalogue do not include all the moral precepts.
On the contrary, The gloss on Mat. 5:11: "Blessed are ye when they shall revile you," etc. says that "Moses, after propounding the ten precepts, set them out in detail." Therefore all the precepts of the Law are so many parts of the precepts of the decalogue.
I answer that, The precepts of the decalogue differ from the other precepts of the Law, in the fact that God Himself is said to have given the precepts of the decalogue; whereas He gave the other precepts to the people through Moses. Wherefore the decalogue includes those precepts the knowledge of which man has immediately from God. Such are those which with but slight reflection can be gathered at once from the first general principles: and those also which become known to man immediately through divinely infused faith. Consequently two kinds of precepts are not reckoned among the precepts of the decalogue: viz. first general principles, for they need no further promulgation after being once imprinted on the natural reason to which they are self-evident; as, for instance, that one should do evil to no man, and other similar principles: and again those which the careful reflection of wise men shows to be in accord with reason; since the people receive these principles from God, through being taught by wise men. Nevertheless both kinds of precepts are contained in the precepts of the decalogue; yet in different ways. For the first general principles are contained in them, as principles in their proximate conclusions; while those which are known through wise men are contained, conversely, as conclusions in their principles.
Reply to Objection 1: Those two principles are the first general principles of the natural law, and are self-evident to human reason, either through nature or through faith. Wherefore all the precepts of the decalogue are referred to these, as conclusions to general principles.
Reply to Objection 2: The precept of the Sabbath observance is moral in one respect, in so far as it commands man to give some time to the things of God, according to Ps. 45:11: "Be still and see that I am God." In this respect it is placed among the precepts of the decalogue: but not as to the fixing of the time, in which respect it is a ceremonial precept.
Reply to Objection 3: The notion of duty is not so patent in the other virtues as it is in justice. Hence the precepts about the acts of the other virtues are not so well known to the people as are the precepts about acts of justice. Wherefore the acts of justice especially come under the precepts of the decalogue, which are the primary elements of the Law.