36 Thus in every age, thanks to the tireless labors of the clergy and also to the cooperation of the laity, the Catholic Church has not only advanced its spiritual kingdom, but has also led nations to increased social prosperity. Everybody knows the social reforms of St. Elizabeth in Hungary, of St. Ferdinand in Castile and of St. Louis IX in France. By their holy lives and zealous labors they brought about salutary improvement in the different classes of society by instituting reforms, by spreading the true faith everywhere, by valiantly defending the Church and above all by their personal example. Nor are We unaware of the excellent merits of the guilds during the Middle Ages. In these guilds artisans and skilled workers of both sexes were enrolled, who, notwithstanding the fact that they lived in the world, kept their eyes fixed upon the sublime ideal of evangelical perfection. Not only did they eagerly pursue this ideal, but together with the clergy they exerted every effort to bring all others to do the same.
Source: Evangelii Praecones (Vatican.va)