7 The right to religious freedom is exercised in human society: hence its exercise is subject to certain regulatory norms. In the use of all freedoms the moral principle of personal and social responsibility is to be observed. In the exercise of their rights, individual men and social groups are bound by the moral law to have respect both for the rights of others and for their own duties toward others and for the common welfare of all. Men are to deal with their fellows in justice and civility. Furthermore, society has the right to defend itself against possible abuses committed on the pretext of freedom of religion. It is the special duty of government to provide this protection. However, government is not to act in an arbitrary fashion or in an unfair spirit of partisanship. Its action is to be controlled by juridical norms which are in conformity with the objective moral order. These norms arise out of the need for the effective safeguard of the rights of all citizens and for the peaceful settlement of conflicts of rights, also out of the need for an adequate care of genuine public peace, which comes about when men live together in good order and in true justice, and finally out of the need for a proper guardianship of public morality. These matters constitute the basic component of the common welfare: they are what is meant by public order. For the rest, the usages of society are to be the usages of freedom in their full range: that is, the freedom of man is to be respected as far as possible and is not to be curtailed except when and insofar as necessary.
Source: Dignitatis Humanae (Vatican.va)