In the early Christian assemblies great use was made of the psalms and canticles in their congregational singing. St. Paul wrote: "Speaking to yourselves in psalms and hymns and spiritual canticles, singing and making melody in your hearts to the Lord" (Ephes. v. 18) "...teaching and admonishing one another in psalms, hymns and spiritual canticles, singing in grace in your hearts to God" (Col. iii. 16). The Jesuit, Father Arevalo, in his _Hymodia Hispanica_, cites many witnesses, such as Clement of Alexandria, the Apostolic Constitutions, Pliny the younger, to prove that hymns were used in the first and second centuries. But a much-debated question is, whether those hymns were really made part of the Office, as hymns stand there to-day. Some scholars deny that they were; others assert that they were certainly part of the Church's Office. All agree that they were certainly in use formally and substantially in the Office in the third and fourth centuries in the Eastern and in the Western Church. The Council of Antioch (269-270) wrote to the Pope that Paul of Samosate had suppressed some canticles recently composed in honour of Jesus Christ. St. Dionysius of Alexandria composed some hymns, to win over an erring bishop. In the fourth century the Council of Laodicea spoke of the introduction of some hymns, which were not approved; and St. Basil tells us that hymns were in universal use in the Eastern Church. In the Western Church, St. Hilary of Potiers (370) composed a hymn book for his church. Its existence is known from the words of St. Jerome. St. Augustine states that St. Ambrose (340-397), shut up with his people in the church in Milan by the persecutors, occupied his flock by their singing of hymns which he himself had composed, and some of which are in our Breviaries. The Church of Milan certainly had hymns in its Office and in its Office books then, for St. Paulinus in his life of St. Augustine wrote: "Hoc in tempore, primum antiphonae, hymni ac vigilae in Ecclesia Mediolanensi celebrari coeperunt; cujus celebritatis devotio usque in hodiernam diem, non solum, in Ecclesia Mediolanensi verum per omnes pene Occidentis provincias manet."