Theodosius Is Baptized, and His Law on the Catholic Faith

About this time Gaul was troubled by the raids of the Alemanni, so Gratian returned to the lands of his father, which he had kept for himself and his brother when he gave the government of Illyria and the Eastern provinces to Theodosius. He accomplished his purpose against the barbarians. Theodosius was just as successful against the tribes from the banks of the Danube: he defeated them, forced them to ask for peace, took hostages from them, and went on to Thessalonica. He fell ill in that city, and after receiving instruction from Ascholius, the bishop, he was initiated, and soon afterward he recovered his health. The parents of Theodosius were Christians and were attached to the Nicene doctrine. He was pleased with Ascholius, who held the same doctrine and was, in a word, endowed with every virtue of the priesthood. He also rejoiced to find that Illyria had had no share in the Arian heresy. He inquired about the religious beliefs held in the other provinces, and learned that as far as Macedonia all the churches were of one mind, and all held that equal honor ought to be given to God the Word and to the Holy Spirit as to God the Father; but that toward the East, and especially at Constantinople, the people were divided into many different heresies. [a]

Theodosius reflected that it would be better to set out his own religious views to his subjects, so as not to seem to be using force by commanding unwilling subjects to worship against their judgment. So he enacted a law at Thessalonica and had it published at Constantinople, knowing well that if the decree went out from that city, which is like a citadel of the whole empire, it would quickly become known in all the other cities. By this law he made known his intention of bringing all his subjects to accept the faith that Peter, the chief of the apostles, had preached to the Romans from the beginning, and that was professed by Damasus, bishop of Rome, and by Peter, bishop of Alexandria. He decreed that the name “catholic church” should belong only to those who gave equal honor to the three Persons of the Trinity, and that those who held the opposite opinions should be treated as heretics, regarded with contempt, and handed over to punishment.