The main characteristic of religious authority that has wide implications for the evolution of different religious authorities from the classical era is the increased emphasis upon monotheism. As Christianity began to take hold, different denominations took on greater authority. The Catholic church operated with a strongly structured hierarchy of "middle men" such as cardinals and bishops who operate as intermediaries under the auspices of the Pope. It was believed that these roles fulfilled a function whereby these men received divine authority from God himself and as such these offices were very powerful and influential and often after being appointed to be a cardinal or bishop these men stayed in these positions their entire lives. This authority is said to derive directly from Scripture and has been justified in this way whenever there is controversy accusing the Church of having too much power.
This idea of divine authority differed from the Protestant denominations who believed that there could not be intermediaries between the Church and God. Some orthodox Christian traditions such as the Greek Orthodox church were known to be fairly stringent in their practices and pressure to conform in their communities. The Greek Orthodox Church took hold in parts of Eastern Europe while Catholicism was prevalent in Western Europe. One prominent difference between Protestant and catholic traditions and Orthodox Christianity is the emphasis of the latter upon the Old Testament, while Catholics and Protestant denominations tended to adopt the New Testament fairly widely, especially after the mid-century.