18 We firmly believe, moreover, that this is the opportune time for the clergy to revive the sodalities and confraternities of the laity to their former honor and glory. Surely, this is a work redounding no less to the well-being of the sodalities than to the universal good of religion. Not to mention other advantages, these sodalities can help you and your clergy not only by carefully cultivating in the people piety and a Christian way of life, but also of strengthening that salutary harmony of mind and heart that we strive for so ardently.
Source: Constanti Hungarorum (Vatican.va)