Since Grundmann, historians have acknowledged that lay piety, like clerical, was marked with veneration for the apostolic life.94 Beginning in the late eleventh century, the growth of cities and literacy both contributed to the need for lay people to have supportive spiritual communities and allowed them to develop those outside the church. Andre Vauchez notes that monastic reform and heresies of the year 1000 shared the view that the only hope for Christianity resided in separation from the material aspects of the secular church and dedication by communities of faith to bring together believers in a reformed way of life.95
Pursuing ideals of poverty and evangelism, however, brought some lay movements into conflict with the church. Once the Gregorian reforms had firmly fixed the clerical perspective, lay religious currents that arose without the direction of the clerical hierarchy came under suspicion. The clergy's distrust of lay religion intensified around the middle of the twelfth century when dissident movements gained strength. Correspondingly, the laity, persuaded by apostolic models ofreform, came to value those above the monastic ideal of obedience and began to lose trust in the clergy, especially its upper ranks. Lay people became increasingly aware of the contradictions they saw between the teachings of the Gospels and the lives of the clergy, enriched materially by some of the reform measures.
Wandering preachers advocated the austerity of the apostolic life and relied on donations to make a living. Some found patrons, such as Robert of Arbrissel did in Bishop Hildebert of Le Mans. Arnold of Brescia, on the other hand, carried his decrial of clerical corruption to the point that he started a popular uprising in 1146, drove the pope out of Rome, and declared a republic there. Condemned in 1139 by Innocent II at the Second Lateran Council and at the Council of Sens in 1140, he was finally excommunicated in 1148, arrested and executed in 1155 under orders of Hadrian IV. Also around mid-century, Peter of Bruys (d. c. 1140) and Henry the monk (d. c. 1145) aroused the indignation of two of the most powerful figures in the Western church: Peter the Venerable, abbot of Cluny, who attacked the Petrobrusians, and Bernard, abbot of Clairvaux, who set out to capture Henry and dissuade his followers. Henry, who eventually died in prison, so aroused the people of Le Mans against clerical authority that they greeted their bishop Hildebert's return by pelting him with mud. Dissident movements continued to gain strength, such that R. I. Moore suggests that between 1179 and 1215 there occurred 'the most rapid diffusion of popular heresy that Western Europe had yet experienced'.96