During the period from the ninth to the fourteenth century, the leading exponents of the doctrine Arguments for ecclesiastical supremacy were Agobard, Bishop of Lyons, Hincmar, Archbishop of Rheims, Pope Nicholas I, Pope Gregory VII, Manegold of Lutterbach, St. Bernard, John of Salisbury, St. Thomas Aquinas, and Pope Innocent III, Pope Gregory, and his school emphasized justitia as the key-note of their policy.
Justitia included papal sovereignty over the church, the liberation of the clergy from lay control, and the right of the pope to correct even kings if they disobeyed the law of Christ. In the famous compilation known as the Decretum of Gratian (twelfth century ), the church authorities were collected and edited and the theory of papal supremacy and the church hierarchy was worked out in terms of a legal system.
The famous document known as the Donation of Constantine, in which the seat of imperial authority was transferred from Rome to Byzantium, and a grant of authority in the west was made to the pope, appeared as early as the ninth century; although it was not interpreted by the church writers to signify that Constantine had granted complete temporal power in the west of the corporate into a later period.
Based on this document, which was incorporated into Gratian’s compilation, the popes traced their claim to temporal sovereignty back to the fourth century. This document was attacked as a forgery as early as the twelfth century but was not generally recognized as spurious until the close of the medieval period. The ablest supporters of papal supremacy avoided the argument based upon Constantine’s grant since by its papal power was derived from man and not from God.
In tracing the arguments that supported the doctrine of ecclesiastical supremacy, it is difficult to separate those whose chief purpose was to elevate the pope to supremacy within the church and those who supported his claim to superiority over the secular authority.
The Petrine theory and the Pseudo-Isidorean Decretals aimed mainly at the former, but indirectly aided the latter, purpose. According to the Petrine theory, St. Peter was the rock upon which the church was built and was given the keys of heaven, with the power to decide on earth who should be bound and loosed in heaven.
The pope, as the successor of St. Peter, who was supposed to have founded the church in Rome and suffered martyrdom there, laid claim to these powers, which were far broader than any that the secular authority could claim. The pseudo-Isidorean decretals were forgeries made in France about the middle of the ninth century, purporting to be documents of the early popes.
They aimed to free the bishops from the control of their archbishops by increasing the authority of the papacy, which the bishops hoped would be less inclined to interfere with them. These documents, with their theory of papal absolutism, were generally accepted and were largely responsible for the establishment of the centralized ecclesiastical monarchy that gave the church such a decided advantage over the decentralized, feudal political system.
The arguments that aimed primarily to justify the supremacy of spiritual over temporal authority followed two main lines. The first was based upon the belief that spiritual authority is by its nature of greater importance and of higher dignity than the secular power. Pope Sylvester urged bishops to remember that the crowns of kings are in comparison with the miters of bishops as lead compared to gold, and Peter Damian described the pope as king of kings and prince of emperors, who excels all men in honor and dignity.
This belief followed naturally from the teachings of the church regarding the relative value of this world and of the world to come and of the things of the flesh and the things of the spirit. Many Scriptural texts were cited to prove the supremacy of the priesthood; and characteristic medieval analogies, such as that of soul and body and sun and moon, were used as arguments to justify the primacy of ecclesiastical rule over temporal authority
The second type of argument asserted that God had conferred upon the church the right to control the actions of secular rulers of morals. As the distinction between clerical and lay elements in the church became drawn, secular rulers, as laymen were excluded from all ecclesiastical functions.
Because of their exalted position, they were especially likely to sin, and the church did not hesitate to apply priestly reproof or censure when the high standard of conduct that it set up for rulers was disregarded. In the Old Testament were found numerous occasions on which the prophets had called down divine wrath upon the kings.
From the New Testament the Petrine theory was interpreted to mean that final authority in disputes among brethren had been conferred upon the pope; and the command of Jesus to Peter, “Feed my sheep,” was held to be a general power of pastoral supervision which included rulers as well as subjects.
In enforcing a penalty against secular rulers for offenses against the church, anathema and excommunication were first tried, by the idea that the church, as the bearer of the sword of the spirit, should impose spiritual penalties. When impious rulers sometimes ignored these decrees, the popes claimed the right to depose the offender and release his subjects from their oaths of allegiance. The religious nature of the feudal oath gave the church an interest in that obligation.
Numerous Scriptural precedents could be found that seemed to justify this action, especially God’s placing of Jeremiah over nations and kingdoms, with authority to root out, pull down, and destroy. Also, the coronation of Charlemagne by the pope was claimed by the church to involve a grant of authority from the pope to the emperor, with the corresponding assertion that the pope could withdraw the power he had conferred.
With a wide basis in custom and public sentiment for the exercise of jurisdiction over many classes of legal controversies; with exclusive control of such as could be shown to be spiritual; with the facility for extending this control that inhered in the doctrine that it embraced whatever actions were in any way tainted with sin and with the power to enforce its interpretation of its authority by the deposition of secular rulers from power the medieval church was in fact, if not in theory, a most potent political institution.