There is no part of ecclesiastical history more curious than the effects of this belief in alternately assisting or impeding the progress of different Churches. In the first three centuries of Christian history, it was the cause of fearful sufferings to the faith; but even then the Christians usually accepted the theory of their adversaries, though they differed concerning its application. Tertullian and Cyprian strongly maintained, sometimes that the calamities were due to the anger of the Almighty against idolatry, sometimes that they were intended to avenge the persecution of the truth. A collection was early made of men who, having been hostile to the Christian faith, had died by some horrible death, and their deaths were pronounced to be Divine punishments.(778) The victory which established the power of the first Christian emperor, and the sudden death of Arius, were afterwards accepted as decisive proofs of the truth of Christianity, and of the falsehood of Arianism.(779) But soon the manifest signs of the dissolution of the Empire revived the zeal of the Pagans, who began to reproach themselves for their ingratitude to their old gods, and who recognised in the calamities of their country the vengeance of an insulted Heaven. When the altar of Victory was removed contemptuously from the Senate, when the sacred college of the vestals was suppressed, when, above all, the armies of Alaric encircled the Imperial city, angry murmurs arose which disturbed the Christians in their triumph. The standing-point of the theologians was then somewhat altered. St. Ambrose dissected with the most unsparing rationalism the theory that ascribed the national decline to the suppression of the vestals, traced it to all its consequences, and exposed all its absurdities. Orosius wrote his history to prove that great misfortunes had befallen the Empire before its conversion. Salvian wrote his treatise on Providence to prove that the barbarian invasions were a Divine judgment on the immorality of the Christians. St. Augustine concentrated all his genius on a great work, written under the impression of the invasion of Alaric, and intended to prove that “the city of God” was not on earth, and that the downfall of the Empire need therefore cause no disquietude to the Christians. St. Gregory the Great continually represented the calamities of Italy as warnings foreboding the destruction of the world. When Rome sank finally before the barbarian hosts, it would seem as though the doctrine that temporal success was the proof of Divine favour must be finally abandoned. But the Christian clergy disengaged their cause from that of the ruined Empire, proclaimed its downfall to be a fulfilment of prophecy and a Divine judgment, confronted the barbarian conquerors in all the majesty of their sacred office, and overawed them in the very moment of their victory. In the conversion of the uncivilised tribes, the doctrine of special intervention occupied a commanding place.