11 It remains for Us now to address the Catholics in a more special manner, and We do so in order that they shouldco-operate with Us in realizing what We have at heart. Christian charity bidseach one labour, according to his opportunities, for the salvation of his fellowmen. We therefore call upon them first of all constantly to offer prayers andsupplications to God, Who alone can give the necessary light to the minds ofmen, and dispose their wills as He pleases. And furthermore, as example is mostpowerful, let them show themselves worthy of the truth which through Divinemercy they possess, and let them recommend the faith which they hold by edifyingand stainless lives. "So let your light shine before men, that they may seeyour good works" (Matth. v., 16). Let them at the same time distinguishthemselves by the practice of virtue in public life, so that it should be moreand more clearly shown that Catholicism cannot be said, without calumny, to runcounter to the interests of the State: but that, on the contrary, nothing elsecontributes so much to the honourable and successful discharge of social duties.
Source: Caritatis Studium (Vatican.va)