30 This right formation of the perfect Christian and citizen, in which the supernatural ennobles all the talents and actions and exalts them, contains also, as is natural, the fulfilment of civil and social duties. Facing the adversaries of the Church, St. Augustine proclaimed in praise of his faith: Give me such fathers of families, such children, such masters, such subjects, such husbands, such spouses, such men of government, such citizens, as those which Christian Doctrine forms, and if you cannot give them, confess that this Christian Doctrine, if practiced, is the salvation of the State ( Epistle cxxxviii. 2).
Source: Firmissimam Constantiam (Vatican.va)