By Sozomen (Ecclesiastical History, Bk. 7, Ch. 21)
About this time the head of John the Baptist, which Herodias had asked of Herod the tetrarch, was removed to Constantinople. It is said that it was discovered by some monks of the Macedonian heresy, who originally dwelt at Constantinople, and afterwards fixed their abode in Cilicia. Mardonius, the first eunuch of the palace, made known this discovery at court, during the preceding reign; and Valens commanded that the relic should be removed to Constantinople. The officers appointed to carry it there, placed it in a public chariot, and proceeded with it as far as Pantichium, a district in the territory of Chalcedon. Here the mules of the chariot suddenly stopped; and neither the application of the lash, nor the threats of the hostlers, could induce them to advance further. So extraordinary an event was considered by all, and even by the emperor himself, to be of God; and the holy head was therefore deposited at Cosilaos, a village in the neighborhood, which belonged to Mardonius.
Soon after, the Emperor Theodosius, impelled by an impulse from God, or from the prophet, repaired to the village. He determined upon removing the remains of the Baptist, and it is said met with no opposition, except from a holy virgin, Matrona, who had been the servant and guardian of the relic. He laid aside all authority and force, and after many entreaties, extorted a reluctant consent from her to remove the head; for she bore in mind what had occurred at the period when Valens commanded its removal. The emperor placed it, with the box in which it was encased, in his purple robe, and conveyed it to a place called Hebdomos, in the suburbs of Constantinople, where he erected a spacious and magnificent temple. The woman who had been appointed to the charge of the relic could not be persuaded by the emperor to renounce her religious sentiments, although he had recourse to entreaty and promises; for she was, it appears, of the Macedonian heresy.
A presbyter of the same tendency, named Vincent, who also took charge of the coffin of the prophet, and performed the sacerdotal functions over it, followed the religious opinions of the emperor, and entered into communion with the Catholic Church. He had taken an oath, as the Macedonians affirm, never to swerve from their doctrines; but he afterwards openly declared that, if the Baptist would follow the emperor, he also would enter into communion with him and be separated. He was a Persian, and had left his country in company with a relative named Addas, during the reign of Constantius, in order to avoid the persecution which the Christians were then suffering in Persia. On his arrival in the Roman territories, he was placed in the ranks of the clergy, and advanced to the office of presbyter. Addas married and rendered great service to the Church. He left a son named Auxentius, who was noted for his very faithful piety, his zeal for his friends, the moderation of his life, his love of letters, and the greatness of his attainments in pagan and ecclesiastical literature. He was modest and retiring in deportment, although admitted to familiarity with the emperor and the courtiers, and possessed of a very illustrious appointment. His memory is still revered by the monks and zealous men, who were all acquainted with him.
The woman who had been entrusted with the relic remained during the rest of her life at Cosilaos. She was greatly distinguished by her piety and wisdom, and instructed many holy virgins; and I have been assured that many still survive who reflect the honorable character which was the result of training under Matrona.
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