The Ecclesiastical History of Sozomen

About this period, a son was born to Valentinian in the West, to whom the emperor gave his own name. Not long after, he proclaimed his son Gratian emperor; this prince was born before his father held the government.

In the meantime, although hailstones of extraordinary magnitude fell in various places, and although many cities, particularly Nicæa in Bithynia, were shaken by earthquakes, yet Valens, the emperor, and Eudoxius, the bishop, paused not in their career, but continued to persecute all Christians who differed from them in opinion. They succeeded to the utmost of their expectations in their machinations against those who adhered to the Nicene doctrines; for throughout the greater time of Valens’ rule, particularly in Thrace, Bithynia, and the Hellespont, and still further beyond, these Christians had neither churches nor priests. Valens and Eudoxius then directed their resentment against the Macedonians, who were more in number than the Christians above mentioned in that region, and persecuted them without measure.

The Macedonians, in apprehension of further sufferings, sent deputies to various cities, and finally agreed to have recourse to Valentinian and to the bishop of Rome rather than share in the faith of Eudoxius and Valens and their followers; and when this seemed favorable for execution, they selected three of their own number,—Eustathius, bishop of Sebaste; Silvanus, bishop of Tarsus; and Theophilus, bishop of Castabalis,—and sent them to the Emperor Valentinian; they likewise intrusted them with a letter, addressed to Liberius, bishop of Rome, and to the other priests of the West, in which they entreated them as prelates who had adhered to the faith approved and confirmed by the apostles, and who before others ought to watch over religion, to receive their deputies with all confirmation, and to confer with them about what should be done in the interval until the affairs of the Church could be approvedly set in order.

When the deputies arrived in Italy, they found that the emperor was in Gaul, engaged in war against the barbarians. As they considered that it would be perilous to visit the seat of war in Gaul, they delivered their letter to Liberius. After having conferred with him concerning the objects of their embassy, they condemned Arius and those who held and taught his doctrines; they renounced all heresies opposed to the faith established at Nicæa; and received the term “consubstantial,” as being a word that conveys the same signification as the expression “like in substance.” When they had presented a confession of faith, analogous to the above, to Liberius, he received them into communion with himself, and wrote to the bishops of the East, commending the orthodoxy of their faith, and detailing what had passed in the conference he had held with them. The confession of faith made by Eustathius and his companions was as follows:—