Antiphonal Hymns against the Ariansintroduced by John. The Interests of the Orthodox are much augmented by the Teachings of John, while the Wealthy are More and More Enraged
The Arians, having been deprived of their churches in Constantinople during the reign of Theodosius, held their churches without the walls of the city. They previously assembled by night in the public porticoes, and were divided into bands, so that they sang antiphonally, for they had composed certain refrains which reflected their own dogma, and at the break of day marched in procession, singing these hymns, to the places in which they held their churches. They proceeded in this manner on all solemn festivals, and on the first and last days of the week.
The sentiments propounded in these odes were such as were likely to engender disputes. As, for instance, the following: “Where are those who say that the Three Persons constitute one Power?” Other similar acrimonious observations were interspersed throughout their compositions. John was fearful lest any of his own church people should be led astray by witnessing these exhibitions, and therefore commanded them to sing hymns in the same manner. The orthodox became more distinguished, and in a short time surpassed the opposing heretics in number and processions; for they had silver crosses and lighted wax tapers borne before them.
The eunuch of the empress was appointed to regulate these processions, to pay the cost of whatever might be required, and to prepare hymns. Hence the Arians, impelled either by jealousy or revenge, attacked the members of the Catholic Church. Much bloodshed ensued on both sides. Briso (for this was the name of the imperial eunuch) was wounded on the forehead by a stone that was cast at him. The resentment of the emperor was kindled, and he put a stop to the Arian assemblies. Having commenced the custom of singing hymns in the manner and from the cause above stated, the members of the Catholic Church did not discontinue the practice, but have retained it to the present day.
The institution of these processions and his services in the Church endeared John to the people; but he was hated by the clergy and the powerful on account of his free boldness, for he never failed to rebuke the clergy when he detected them in acts of injustice, nor to exhort the powerful to return to the practice of virtue when they abused their wealth, committed impiety, or yielded to voluptuousness.
Source: Ecclesiastical History (New Advent)