The called Middle Ages was a time marked by the outbreak of resistance movements which had as main and common characteristic the opposition to the stance adopted by the Roman Catholic Church during this period of history. The target of this research is to identify the main features of the clergy in this period, as well as identify what were these resistance movements and their theological basis. The method adopted here is to search for bibliographical material, establishing as the main base, notably the writings of the theologian José Comblin, who produced vast material on this issue. As result of this work, it could be detected that these movements occurred in a profuse way. Over that, it was also evident in this search result that power centralization, enrichment and inattention to the reality of the poor, all these outstanding features in the behavior of the Catholic Church in the period were elements that constituted the main cause of the outbreak of such movements.
