It is not the part of prudence to neglect that which antiquity in its long experience has approved and which is also taught by apostolic authority.
Pope Leo XIIIRemember and understand well that where Peter is, there is the Church; that those who refuse to associate in communion with the Chair of Peter belong to Antichrist, not to Christ. He who would separate himself from the Roman Pontiff has no further bond with Christ.
Pope Leo XIIINo human law can abolish the natural and original right of marriage, nor in any way limit the chief and principal purpose of marriage ordained by Godโs authority from the beginning: โIncrease and multiply.
Pope Leo XIIIThe sacred rites, although not instituted specifically for proving the truth of the dogmas of the Catholic Faith incontrovertibly, are effectively the living voice of Catholic Truth, the oft-sounded expression of it. For that very reason the true Church of Christ, even as she shows great zeal to guard inviolate those forms of divine worship - since they are hallowed and are not to be changed - sometimes grants or permits something novel in the performance of them in certain instances. This she does especially when they are in conformity with their venerable antiquity.
Pope Leo XIII