SERDICA (Sardica). - Today Sofia. Its name derives from the Thracian tribe of the Serdi (Cassius Dio, LI, 25). In the arrangement given by Trajan to the Dacian region after the conquest, it took the name Ulpia Serdica.
From the 3rd century it was assigned to Lower Dacia. Sacked by Attila, it was subsequently provided by Justinian with fortifications, of which the ruins remain, for the defense of the territory (Procopius, De Aed., 4, 1; 4, 4). Given its position in the great Illyricum on the border between the two portions, western and eastern, of the Empire, it was, like the whole Danubian region, the seat of legionary formations recruited on the spot. Many imperial constitutions collected in the Theodosian Code are dated from S. Natives of S. were the two emperors Galerius and Maximinus Daia.
The council of S. - A synod was held, most probably in 343 (Mansi; Hefele-Leclercq in 344; E. Schwartz in 342), convoked by Constans I and Constantius II at the initiative of Pope Julius I. About 180 bishops hastened there, among them about 80 Orientals adhering to Semi-Arianism. It was Hosius of Cordoba who presided over it, assisted by the papal legates, the presbyters Archidamus and Philoxenus. The synod was an energetic reaffirmation of Nicene orthodoxy against the spreading of Semi-Arianism.
The Semi-Arian bishops, taking occasion from the presence at the synod of St. Athanasius, of Marcellus of Ancyra and of Asclepiades of Gaza, whom they regarded as deposed, formed not far from S. a conciliabulum that excommunicated Pope Julius, Hosius and others and promulgated a new dogmatic symbol that links up with the 4th Antiochene formula of 341.
The legitimate Council of S., on the other hand, reconfirmed the orthodoxy and legitimacy of St. Athanasius, of Asclepiades and of Marcellus, deposed certain Semi-Arian bishops such as Theodore of Heraclea and Basil of Ancyra, reconfirmed the Symbol of Nicaea after setting aside the proposal of a new one, prepared the date of Easter for the next 50 years and promulgated 20 disciplinary canons. These regulate episcopal law. Of singular importance are canons 3-5, in which the right is recognized for the bishop of Rome to annul the decrees issued against a bishop by a provincial synod and to appoint new judges for the review of the case. The Westerners associated the canons of S. with those of Nicaea, which gave rise to the misunderstanding concerning their origin. The council of S. did not have the effect of restoring concord, yet it succeeded in galvanizing for the time being the orthodoxy of the West and in making it manifest to the scarcely orthodox Constantius II.
Bibliography2 works
Ignazio Ortiz de Urbina