11 Let them rather act in the closest concert in order to oppose all theirplans and strength to the wickedness of Socialism, which very clearly will causeevils and great losses. For it is constantly and in every way exerting itselfviolently against religion and the state; it is striving every day to throw bothdivine and human laws into confusion and to destroy the good works ofevangelical providence. Our voice has been raised often and vehemently againstthis great calamity, as the commands and warnings which We gave in the Letter Rerum Novarum sufficiently testify. So to this purpose all good men should direct their minds to the exclusion of factional interests. They should uphold the sacred order of God and of their country without doubt, in their legitimate fight on behalf of Christian truth, justice, and charity. For it is from this order that public safety and happiness spring.
Source: Permoti Nos (Vatican.va)