ORIGINS AND VOCATION OF CHRISTIAN SACRED CHANT

Pliny the Younger, proconsul of Bithynia and Pontus from 111 to 112, reported to the emperor Trajan about people "who gather on the day of the sun, before dawn, to sing together in honour of Christ, as if he was a God" (Pliny the Younger, Epistles, Book X, letter 96). This was the first thing that a heathen noted of a meeting of Christians in the early centuries of Christianity. 

They sang "psalms, hymns and spiritual songs", as a few years earlier, Paul had advised to the Christians of those regions, Ephesians and Colossians (Col 3:16), because "singing is a sign of the joy of the heart" (Acts 2:46). St. Jerome (4th century) refers of Christian communities "where in the likeness of a thunder of heaven, the Amen so resounds that the futile temples of the idols are shattered" (St. Jerome, in Galatians 2, r; PL 26, 355c). 

These authors reveal to us that the praise sung by the first Christian communities was one of their distinctive features, and that it was expressed with great fervour and strength.