Reply Obj. 1: Virtue is twofold, as explained above (Q. 63, A. 2), viz. acquired and infused. Now the fact of being accustomed to an action contributes to both, but in different ways; for it causes the acquired virtue; while it disposes to infused virtue, and preserves and fosters it when it already exists. And since law is given for the purpose of directing human acts; as far as human acts conduce to virtue, so far does law make men good. Wherefore the Philosopher says in the second book of the Politics (Ethic. ii) that "lawgivers make men good by habituating them to good works."
Reply Obj. 2: It is not always through perfect goodness of virtue that one obeys the law, but sometimes it is through fear of punishment, and sometimes from the mere dictates of reason, which is a beginning of virtue, as stated above (Q. 63, A. 1).
Reply Obj. 3: The goodness of any part is considered in comparison with the whole; hence Augustine says (Confess. iii) that "unseemly is the part that harmonizes not with the whole." Since then every man is a part of the state, it is impossible that a man be good, unless he be well proportionate to the common good: nor can the whole be well consistent unless its parts be proportionate to it. Consequently the common good of the state cannot flourish, unless the citizens be virtuous, at least those whose business it is to govern. But it is enough for the good of the community, that the other citizens be so far virtuous that they obey the commands of their rulers. Hence the Philosopher says (Polit. ii, 2) that "the virtue of a sovereign is the same as that of a good man, but the virtue of any common citizen is not the same as that of a good man."
Reply Obj. 4: A tyrannical law, through not being according to reason, is not a law, absolutely speaking, but rather a perversion of law; and yet in so far as it is something in the nature of a law, it aims at the citizens' being good. For all it has in the nature of a law consists in its being an ordinance made by a superior to his subjects, and aims at being obeyed by them, which is to make them good, not simply, but with respect to that particular government. ________________________
SECOND ARTICLE [I-II, Q. 92, Art. 2]
Whether the Acts of Law Are Suitably Assigned?
Objection 1: It would seem that the acts of law are not suitably assigned as consisting in "command, prohibition, permission, and punishment." For "every law is a general precept," as the Jurist states. But command and precept are the same. Therefore the other three are superfluous.
Obj. 2: Further, the effect of a law is to induce its subjects to be good, as stated above (A. 1). But counsel aims at a higher good than a command does. Therefore it belongs to law to counsel rather than to command.
Obj. 3: Further, just as punishment stirs a man to good deeds, so does reward. Therefore if to punish is reckoned an effect of law, so also is to reward.
Obj. 4: Further, the intention of a lawgiver is to make men good, as stated above (A. 1). But he that obeys the law, merely through fear of being punished, is not good: because "although a good deed may be done through servile fear, i.e. fear of punishment, it is not done well," as Augustine says (Contra duas Epist. Pelag. ii). Therefore punishment is not a proper effect of law.