Reply Obj. 2:  As stated above (Q. 96, A. 6), human laws fail in some cases:  wherefore it is possible sometimes to act beside the law; namely, in a case where the law fails; yet the act will not be evil.  And when such cases are multiplied, by reason of some change in man, then custom shows that the law is no longer useful:  just as it might be declared by the verbal promulgation of a law to the contrary.  If, however, the same reason remains, for which the law was useful hitherto, then it is not the custom that prevails against the law, but the law that overcomes the custom:  unless perhaps the sole reason for the law seeming useless, be that it is not “possible according to the custom of the country” [Q. 95, A. 3], which has been stated to be one of the conditions of law.  For it is not easy to set aside the custom of a whole people.

Reply Obj. 3:  The people among whom a custom is introduced may be of two conditions.  For if they are free, and able to make their own laws, the consent of the whole people expressed by a custom counts far more in favor of a particular observance, that does the authority of the sovereign, who has not the power to frame laws, except as representing the people.  Wherefore although each individual cannot make laws, yet the whole people can.  If however the people have not the free power to make their own laws, or to abolish a law made by a higher authority; nevertheless with such a people a prevailing custom obtains force of law, in so far as it is tolerated by those to whom it belongs to make laws for that people:  because by the very fact that they tolerate it they seem to approve of that which is introduced by custom. ________________________

FOURTH ARTICLE [I-II, Q. 97, Art. 4]

Whether the Rulers of the People Can Dispense from Human Laws?

Objection 1:  It would seem that the rulers of the people cannot dispense from human laws.  For the law is established for the “common weal,” as Isidore says (Etym. v, 21).  But the common good should not be set aside for the private convenience of an individual:  because, as the Philosopher says (Ethic. i, 2), “the good of the nation is more godlike than the good of one man.”  Therefore it seems that a man should not be dispensed from acting in compliance with the general law.

Obj. 2:  Further, those who are placed over others are commanded as follows (Deut. 1:17):  “You shall hear the little as well as the great; neither shall you respect any man’s person, because it is the judgment of God.”  But to allow one man to do that which is equally forbidden to all, seems to be respect of persons.  Therefore the rulers of a community cannot grant such dispensations, since this is against a precept of the Divine law.

Obj. 3:  Further, human law, in order to be just, should accord with the natural and Divine laws:  else it would not “foster religion,” nor be “helpful to discipline,” which is requisite to the nature of law, as laid down by Isidore (Etym. v, 3).  But no man can dispense from the Divine and natural laws.  Neither, therefore, can he dispense from the human law.