There are some who become fearful and hesitant when faced with the wickedness of Communism, which aims to rob the faith from those very people to whom it promises material prosperity. . . . Others show themselves no less timid and hesitant in the face of that economic system which is known as Capitalism. The Church has not failed to denounce the grave consequences that can follow from it.
The Church has not only called attention to the wrong use of capital and of the right to property promoted and defended by this system, but has insisted just as much that capital and private property must be a means of production for the benefit of the whole of society and of sustaining and defending the freedom and dignity of the human person.
The errors inherent in both economic systems should convince everybody, priests in particular, that they ought to uphold faithfully the social teaching of the Church, to spread the knowledge of it and to show how its can be applied in practice. This teaching is the only remedy for the evils we have denounced, evils, unhappily, so widespread. This teaching shows the unity and perfection of the demands of justice and the duties of charity, and promotes a social order which does not serve to oppress individuals and isolate them in blind selfishness but brings everybody together in harmony and in the bonds of close brotherhood.
Pope Pius XII, Apostolic Exhortation to the Priess of the World, September 25, 1950