Final answer:
The idea expressed by Pope Gelasius I about the dual authority in Europe facilitated the Catholic Church's power over spiritual and political matters, affecting all areas of life from governance to education and social legitimacy.
Step-by-step explanation:
Impact of Papal Authority on European Society
The quote from Pope Gelasius I highlights the dual system of governance in medieval Europe: the sacred authority of the priesthood and the authority of kings. This structure deeply influenced European society, with the church asserting significant control over both spiritual and temporal matters. The ability to excommunicate individuals placed the church, at times, above the monarchy, as seen during the Investiture Controversy when Pope Gregory VII excommunicated Holy Roman Emperor Henry IV. Similarly, through the Donation of Constantine (albeit a forged document), and the Petrine Succession, the papacy justified its influence. Furthermore, the church facilitated literacy and knowledge preservation, unified Europe through Latin, and as with Pope Leo III crowning Charlemagne, also legitimized rulers.
The church's influence was both spiritual and political, playing a crucial role in administration and education, as bishops and monasteries supported new elites. The coronation of rulers by the pope, as with Charlemagne, meant that rulers often had to align with the church for legitimacy. Simultaneously, the church's multinational bureaucracy gave it a recurring and profound interaction with society's individuals, surpassing the interaction level between feudal lords and their vassals.