Thoughtful men, with hearts craving the truth, have come to seek in the Catholic Church the road which leads with surety to eternal life. They have understood that they could not cleave to Jesus Christ as the Head of the Church if they did not belong to the Body of Jesus Christ which is the Church. Nor could they ever hope to possess in all its purity the faith of Jesus Christ if they were to reject its legitimate teaching authority entrusted to Peter and his successors.
Pope Leo XIIINot only, in strict truth, was marriage instituted for the propagation of the human race, but also that the lives of husbands and wives might be made better and happier. This comes about in many ways: by their lightening each other's burdens through mutual help; by constant and faithful love; by having all their possessions in common; and by the heavenly grace which flows from the sacrament.
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