Question: In his high school history course, my son was told that in the middle ages bishops were ordained by the ruling nobility. Doesn't that invalidate the concept of apostolic succession?
Answer: Under the medieval feudal system bishops were granted landed estates and given authority to conduct the secular government within their territory. In this respect, they were like the lay nobles who received their lands and authority in the same way. Quite understandably, the king or lesser noble making such a grant felt that he had a right to some say about who was to be appointed to his bishoprics. Great wealth and the stability of government were often involved. For the most part, though, the king would allow the bishop to be elected by the people of the diocese or the cathedral chapter, reserving only a right to veto elections of candidates he deemed unsatisfactory. (In some cases the election also had to be approved by a church superior; bishops by the metropolitan archbishop, archbishops by the Pope -- so, three separate factions had to concur in the election before it was conclusive.)
The abbots of monasteries often had to undergo approval by the noble for the same reasons as bishops. But by the tenth Century the founding benefactors of many monasteries recognized the need to make their foundations free from secular control, and even from the control of the local bishop. Cluny, founded in 910 is probably the first, and certainly the most well known example. In such "exempt" monasteries the monks were free to run their own affairs, subject only to the control of the Holy See. At least one house, that of Frutturia, founded by William of Volpiano in 1000, "was to be God's property alone."1
In medieval society nobles received their lands and their secular authority from their superiors in a ceremony. A pledge of loyalty was made to the superior, by which one became his "vassal." This pledge obligated the vassal to give the superior a portion of the revenues produced from the land and to support him with military service when that became necessary. To show his acceptance of the vassal's pledge, the superior would invest him with a token or tokens of his delegated authority. It might literally be a clod of soil from the land, or perhaps a weapon or a shield. In the case of bishops, the symbol was more likely to be a ring or a staff. In medieval times these were symbols of secular jurisdiction and lacked the purely religious character they have today.
In any event, no bishop functioned sacramentally until he had received ordination and/or episcopal consecration at the hands of other bishops. This concept of "lay investiture" followed by sacramental consecration was clearly understood in the medieval mind, but has, perhaps, become a bit opaque to those with a poor knowledge of Catholicism or feudalism.
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