Let us not be too harsh. Those early church leaders were actually quite concerned that a zealous "layman" would excercise such power over a domain that was not his. The Christian cultural concept of "separation of Church and State" can be traced to this concern.
The early church leaders concern was well-founded...
The Papacy soon evolved unchallenged to eventually doubly impose its unscrupulous will and power during the entire medieval period "in the name of Christ" as both 'Pope' and 'Emperor.'