It is evident that the fourth century was one of innovation in the
custom of congregational singing as the Ambrosian hymn was more widely
diffused. Our knowledge of what actually took place is very incomplete,
based first upon the writing of Ambrose and his contemporaries and later
upon the hints derived from monastic usage. That morning and evening
services of prayer and praise were common is well known. That the
singing of the new fourth century hymns was an integral part of such
services is largely assumed. Prudentius wrote hymns for the evening
ceremony of the lucernare or lighting of the candles, a Christian
practice adopted from the Greek church, to which many references are
found. The fact that the hymns of Prudentius were in existence long
before they appeared in the records of formal worship points to early
Christian usage, however dimly perceived.
Concerning music we learn from the most recent researches that “nothing
definite is known of the melodies that were actually applied to the
hymns of St. Ambrose.”[11] The traditional liturgical music of Milan is
known as the Ambrosian Chant. It cannot be traced to Ambrose himself but
is supposed to have existed in a simpler form than that which appears in
available manuscripts beginning with the twelfth century. At least it
may be said to have existed prior to the Roman Chant and perhaps have
influenced the latter. With a frank acknowledgement of ignorance as to
the antiphonal melodies which thrilled St. Augustine at Milan, the
possibility must be admitted that they reflected to some extent the
formal music of the synagogue or the music of the Greeks or the elements
of contemporary folk music because these were the musical materials of
which the Christians had experience. All three may have been
represented, but for a hymn of the Ambrosian type, the chant as evolved
in rendering the Gospels or the Psalms may have given place to a form of
song more characteristic of the lyric.