"Religious Socialism," "Christian Socialism," are expressions implying a contradiction in terms.
Pope Pius XICapitalism itself is not to be condemned. And surely it is not vicious of its very nature, but it has been vitiated.
Pope Pius XIIf our age in its pride laughs at and rejects Our Lady's Rosary, a countless legion of the most saintly men of every age and of every condition have not only held it most dear and have most piously recited it but have also used it at all times as a most powerful weapon to overcome the devil, to preserve the purity of their lives, to acquire virtue more zealously, in a word, to promote peace among men.
Pope Pius XICatholics can in no way convince themselves that so enormous and unjust an in equality in the distribution of this world's goods truly conforms to the designs of the all-wise Creator.
Pope Pius XIAlways moved by religious motives, the Church has condemned the various forms of Marxist Socialism; and she condemns them today, because it is her permanent right and duty to safeguard men from currents of thought and influence that jeopardize their eternal salvation.
Pope Pius XIFor they have always unanimously maintained that nature, rather the Creator Himself, has given man the right of private ownership not only that individuals may be able to provide for themselves and their families but also that the goods which the Creator destined for the entire family of mankind may through this institution truly serve this purpose.
Pope Pius XI