We ought to fast, and to abstain from all vice, and from all that will lead us into sin, as well as from extravagance and superfluity. We should often visit the churches, and venerate and reverence all ecclesiastics on account of their office, and because they distribute the Sacred Body and Blood of Christ, which they offer in sacrifice, receive themselves, and administer to others. And let everyone know and hold for certain that we cannot be saved except through the sacred Words and the Precious Blood of our Lord Jesus Christ, which priests preach, announce, and distribute, and of which they are the sole ministers.
–Saint Francis of Assisi (1181–1226)