In addition to what has already been given on this subject, it may be proper to add the directions of the various councils respecting the observance of the feast. A canon of the Council of Macon (A.D. 581) enjoins that from the Feast of St. Martin (Nov. 11) to the Nativity there be fasting on Monday, Wednesday, and Friday of each week, and that the canons be then read; also that the sacrifices be offered in the Quadragesimal order. In the second Council of Tours (567), the fast of three days in the week is ordered for the months of September, October, and November, and from Dec. 1 to. the Nativity every day. But this is for monks oily. It seems, from all that is certainly known, that Advent took its place among. Church seasons only in the latter part of the 6th century. Once established as one of the great festivals, it was felt that its dignity demanded a season of preparation. Originally left to the discretion of the faithful, the number of days or weeks to be set apart was eventually defined by rule, and at first, it seems, in the churches of Gaul. Yet the same rule did not everywhere prevail, for the oldest Gallican sacramentary shows .three Sundays in Advent, and the Gothic-Gallican only two. But the rule that the term of preparation should be a quadragesima, to commence after the Feast of St. Martin, implies six Sundays. This rule-not enacted, but re-enforced, by the Canon of Macon (581)-obtained in other churches, as appears from the fact that the Ambrosian (or Milan) and Mozarabic (or Spanish) Ordo shows six missae implying that number of Sundays, and the same rule was observed in some of the Gallican churches. The rule-not of Advent, but of this quadragesima-is first met with in the diocese of Tours. The observance of the Quadragesima Apostolorum and Quadragesinua S. Philippi (ii the. Greek calendar Nov. 14) is enjoined upon monks by Nicephorus, patriarch of Constantinople' (806). The Church of Rome, under Gregory, at the close of the 6th century, received the season of preparation as an ecclesiastical rule, restricted in its proper sense to the four Sundays before the Nativity, and this became the general rule for the Western Church throughout the 8th century and later. The Sacramentary of Gelasius, a Lectionary written for Charlemagne by Paul the Deacon, and other older works, all give five Sundays. This seeming discrepancy is easily explained, since the fifth Sunday before the Nativity was not considered as itself a Sunday in Advent, but as the preparation for Advent.
After the pattern of the Lenten fast, Advent was marked as a season of mourning in the public services of the Church. The custom of omitting the Gloria in Excelsis, and also: the Te Deum and Ite Missa Est, and of laying aside the dalmatic and subdeacon's vestment, was coming into use during the 8th century. The Benedictine monks retained the Te Deum in Advent as in Lent, alleging the rule of their founder. The Alleluia also, and the sequences, as also the hymns, were omitted, but not in all churches. In some churches the Miserere (Psalm li) and other mournful psalms were added to or substituted for the ordinary psalms. For lessons, Isaiah was read all through, beginning on Advent Sunday. When that was finished, the twelve minor prophets followed, or readings from the fathers, especially the epistles of pope Leo on the incarnation and sermons of St. Augustine.
In the Greek Church the .season of preparation for the Nativity is of late introduction.- No notice of it occurs in the liturgical works of Theodore Studites, though the forty days fast of St. Philip was enjoined (upon monks) by Nicephorus. This forty days' fast, beginning Nov. 14, is now the rule of the Greek Church. In the separated churches f. the East no trace appears, within our period, of an Advent season, unless we except the existing Nestorian or Chaldsean rule, in which the liturgical year begins with four Sundays of Annunciation before the Nativity. The Armenian Church, refusing to accept Dec. 25 as the Feast of the Nativity, and adhering to the more ancient sense of the Feast of Epiphany as including the birth of Christ, prepares for this high festival (Jan. 6) by a fast of fifty days, beginning Nov. 17.