It is neither just nor human so to grind men down with excessive labour as to stupefy their minds and wear out their bodies.
Pope Leo XIIIYou are not to be looked upon as holding the true Catholic faith if you do not teach that the faith of Rome is to be held
Pope Leo XIIIInasmuch as the domestic household is antecedent, as well as in idea as in fact, the family must necessarily have rights and duties which are prior than those of the Community and founded more immediately in nature.
Pope Leo XIIIThe liberty of thinking and publishing whatsoever each one likes, without any hindrances, is not in itself an advantage over which society can wisely rejoice. On the contrary, it is the fountainhead and origin of many evils.
Pope Leo XIII