If Socialism, like all errors, contains some truth (which, moreover, the Supreme Pontiffs have never denied), it is based nevertheless on a theory of human society peculiar to itself and irreconcilable with true Christianity. Religious socialism, Christian socialism, are contradictory terms; no one can be at the same time a good Catholic and a true socialist.
Pope Pius XIJustice requires that to lawfully constituted Authority there be given that respect and obedience which is its due; that the laws which are made shall be in wise conformity with the common good; and that, as a matter of conscience all men shall render obedience to these laws.
Pope Pius XINo vicarious charity can substitute for justice which is due as an obligation and is wrongfully denied.
Pope Pius XIThis [the opening of the Vatican City radio station built by Marconi earlier in 1931] was a new demonstration of the harmony between science and religion that each fresh conquest of science ever more luminously confirms, so that one may say that those who speak of the incompatibility of science and religion either make science say that which it never said or make religion say that which it never taught.
Pope Pius XITherefore the dignity of the human person normally demands the right to the use of earthly goods as the natural foundation for a livelihood; and to that right corresponds the fundamental obligation to grant private property, as far as possible, to all.
Pope Pius XIThese principles with due regard to time and place, must, in accordance with Christian prudence, be applied to all schools, particularly in the most delicate and decisive period of formation, that, namely, of adolescence; and in gymnastic exercises and deportment special care must be had of Christian modesty in young women and girls which is so gravely impaired by any kind of exhibition in public.
Pope Pius XI