THE modern entertainment called opera is a child of the Roman Catholic Church. What might be described as operatic tendencies in the music of worship date further back than the foundation of Christianity. The Egyptians were accustomed to sing "jubilations" to their gods, and these consisted of florid cadences on prolonged vowel sounds. The Greeks caroled on vowels in honor of their deities. From these practices descended into the musical part of the earliest Christian worship a certain rhapsodic and exalted style of delivery, which is believed to have been St. Paul's "gift of tongues."That this element should have disappeared for a considerable time from the church music is not at all remarkable, for in the first steps toward regulating the liturgy simplification was a prime requisite. Thus in the centuries before Gregory the plain chant gained complete ascendancy in the church and under him it acquired a systematization which had in it the elements of permanency.Yet it was through the adaptation of this very chant to the delineation of episodes in religious history that the path to the opera was opened. The church slowly built up a ritual which offered no small amount of graphic interest for the eyes of the congregation. As ceremonials became more and more elaborate, they approached more and more closely the ground on which the ancient dramatic dance rested, and it was not long before they themselves acquired a distinctly dramatic character. It is at this point that the liturgical ancestry of the opera becomes quite manifest. The dance itself, at first an attempt to delineate dramatically by means of measured movement, and thus the origin of the art of dramatic action, was not without its place in the early church. The ancient pagan festivals made use of the dance, and the early Christians borrowed it from them. At one time Christian priests executed solemn dances before their altars just as their Greek predecessors had done. But in the course of time the dance became generally practised by the congregation and this gave rise to abuses. The authorities of the church abandoned it. But the feeling for it lingered, and in after years issued in the employment of the procession. When the procession left the sanctuary and displayed itself in the open air, something of the nature of the dance returned to it and its development into a dramatic spectacle was not difficult.