A brief overview of the Church's Advent season.
39. Advent has a twofold character, for it is a time of preparation for the Solemnities of Christmas, in which the First Coming of the Son of God to humanity is remembered, and likewise a time when, by remembrance of this, minds and hearts are led to look forward to Christ's Second Coming at the end of time. For these two reasons, Advent is a period of devout and expectant delight.
40. Advent begins with First Vespers (Evening Prayer I) of the Sunday that falls on or closest to 30 November and it ends before First Vespers (Evening Prayer I) of Christmas.[R8]
41. The Sundays of this time of year are named the First, Second, Third, and Fourth Sundays of Advent.
42. The weekdays from 17 December up to and including 24 December are ordered in a more direct way to preparing for the Nativity of the Lord.
V. The Arrangement And Ornamentation Of Churches For The Celebration Of The Eucharist
305. Moderation should be observed in the decoration of the altar.
During Advent the floral decoration of the altar should be marked by a moderation suited to the character of this time of year, without expressing in anticipation the full joy of the Nativity of the Lord. During Lent it is forbidden for the altar to be decorated with flowers. Exceptions, however, are Laetare Sunday (Fourth Sunday of Lent), Solemnities, and Feasts.
Floral decoration should always show moderation and be arranged around the altar rather than on the altar table.