Final answer:
The model of the kingly role for Church leaders is rooted in historical events such as the coronation of Charlemagne by Pope Leo III, the investiture controversy, and the doctrine of Petrine Succession. It involves the assertion of church independence and the clerical roles in legitimizing secular power and governance.
Step-by-step explanation:
The model of the kingly role to be taken by Church leaders, as exemplified by historical precedents, indicates that these leaders were envisioned as having a divine mandate to rule. This began with Pope Leo III's coronation of Charlemagne, reinforcing the idea that kings held their authority by virtue of papal consent. However, secular rulers often contested this, leading to the investiture controversy, where the church sought to end simony and enforce clerical celibacy, thus asserting its independence from monarchical control. The church's power was further solidified when a king who interfered with church appointments risked being excommunicated, thereby delegitimizing their rule.
Christianity also played a role in legitimizing new rulers. Germanic kings, such as Charlemagne, used conversion to Catholic Christianity to better integrate with their Roman subjects. The bishops, often acting as administrators, and monasteries as educational centers, were instrumental in aiding the process of governance and the stabilization of rule.
Papal power grew from the symbolic significance of Rome and the doctrinal tie to the Apostle Peter, known as Petrine Succession. Over time, the pope's role as the leader of the church solidified, and by the mid-fifth century CE, the pope was claiming total authority over the western church hierarchy.