'The Pilgrim Church': The Union of Church and State

Here's an excerpt from 'The Pilgrim Church' by E.H. Broadbent in which we see the church uniting with the Roman State and then the fall of Rome:

This second period of the history of some of the churches, beginning with Constantine's edict of toleration in 313, is of lasting importance because it exhibits the experiment on a large scale, of the union of Church and State. Could the Church, by union with the world, save it?

The Roman world[16] had reached its greatest power and glory. Civilization had attained to the utmost of which it was capable apart from the knowledge of God. Yet the misery of the world was extreme. The luxury and vice of the rich were boundless; a vast proportion of the people were slaves. The public exhibitions, where the sight of every kind of wickedness and cruelty amused the populace, deepened the degradation. There was still vigour at the extremities of the Empire, in conflict with surrounding enemies, but disease at the heart threatened the life of the whole body, and Rome was helplessly corrupt and vicious.

As long as the Church had remained separate it had been a powerful witness for Christ in the world, and was constantly drawing converts into its holy fellowship. When, however, already weakened by the adoption of human rule in place of the guidance of the Spirit, it was suddenly brought into partnership with the State, it became itself defiled and debased. Very soon the clergy were competing for lucrative
positions and for power as shamelessly as the court officials, while, in congregations where a godless element predominated, the material advantages of a profession of Christianity changed the purity of the persecuted churches into worldliness. The Church was thus powerless to stem the downward course of the civilised world into corruption.

Ominous clouds, threatening judgment, were gathering. In distant China movements of the population, setting westward, led to a great migration of the Huns, who crossed the Volga, and, pressing upon the Goths in what is now Russia, forced them on to the frontiers of the Empire, which was by this time divided; the Eastern part, or Byzantine Empire, having Constantinople as its capital, and the Western, Rome. The Germanic or Teutonic nations came out of their forests. Pressed by the Mongol hordes
from the East, and attracted by the wealth and weakness of the Empire, Goths (divided into Eastern and Western under the names of Ostrogoths and Visigoths) and Germanic peoples such as the Franks, Vandals, Burgundians, Suevi, Heruli, and others, broke like the waves of some resistless flood over the doomed civilization of Rome. In one year great provinces such as Spain and Gaul were destroyed. The inhabitants, long accustomed to peace, congregated mostly in the cities for the sake of the ease and pleasure afforded there, saw the armies which had so long guarded their frontiers disappear; the cities were wiped out, and a cultivated and luxurious population, which had avoided the discipline of military training, was massacred or enslaved by Pagan barbarians. Rome itself was captured by the Goths under Alaric (410), and that great city was plundered and desolated by barbarian hosts. In 476 the Western Roman Empire came to an end, and in the vast regions where it had so long reigned, new kingdoms began to grow up. The Eastern part of the Empire continued, until, in 1453, nearly a thousand years later, Constantinople was captured by the Mohammedan.