4. A voiding law sometimes directly affects the act, and makes it of no effect, as does an impediment of marriage; sometimes it immediately affects the capacity of the person, as ecclesiastical law deprives religious who are solemnly professed of the capacity to make a valid will; sometimes it annuls an act destitute of certain formalities, as a clandestine contract of marriage.
5. If a voiding law also prohibits the acts which it annuls, it binds subjects not to perform such actions; charity and justice require also that a lawyer employed to make a will should draw it validly according to the law; otherwise one who performs an act made void by law, but which is not morally wrong or injurious to others, does not commit a sin.
6. Neither ignorance, nor grave fear, nor serious private inconvenience avail to make valid an act which has been made void by the law. For none of these causes affects the objective validity of the act which the law strikes at for the common good. If, however, a voiding law causes great public inconvenience, then it ceases to be for the common good; it ceases to be useful, and thereby ceases to be a law with binding force.
SECTION V
On Civil or Municipal Law
i. The civil authority has full power to make laws in order to the attainment of its own special end, which is the common temporal welfare of its subjects. If these laws are just, they cannot be ignored by the moral theologian, for very many practical questions will depend on them for their solution. When the classical authors published their folios on moral theology, they appealed for the most part to the jus commune, the common law of Christendom, which was the Roman civil law slightly modified by local enactments and customs. Nowadays this cannot be done. The unity of Christendom with its common, universally accepted stock of ideas and laws, no longer exists, and regard must be paid to municipal or local law. Especially in England and in America must this be done, for the system of law which is in force among us is distinct from the Roman civil law, and from thk modern European systems which are largely based upon it.
In this section, then, we will consider the bearing of English law on questions of conscience, and try to lay down certain general principles which will guide us towards the solution of particular cases as they arise.
We saw above that the legislative authority in civil matters
