78 Those who act otherwise, and at the same time fondly pretend to attain their objective with purely political or economic means, are in the grip of a dangerous error. When religion is banished from the school, from education and from public life, when the representatives of Christianity and its sacred rites are held up to ridicule, are we not really fostering the materialism which is the fertile soil of Communism.? Neither force, however well organized it be, nor earthly ideals however lofty or noble, can control a movement whose roots lie in the excessive esteem for the goods of this world.
Source: Divini Redemptoris (Vatican.va)