In Rome the season evolved to a four-week preparation whose focus was on the joyful celebration of the Lord's Incarnation. In Gaul there was a longer, heavily penitential season emphasizing the Lord's glorious advent at the end of time as Lord of history and judge of the universe. Roman practice from the 12 th century, codified by the Council of Trent and enhanced by the greatly enriched lectionary of Vatican Council II, combines these different emphases. The Alleluia is retained before the Gospel. There has been no mandatory Advent fast since the 1917 Code of Canon Law.
Advent is a time for looking both backward and forward.
We look backward as we prepare to celebrate the historical birth of Jesus of Nazareth at Christmas. Before that birth people longed for the Messiah who would restore Israel to her former power. We identify with that ancient longing for restoration as we await Christ's coming more fully into our lives and also as we await His 2nd coming. With that longing for restoration in mind, we recognize in Advent a time of preparation and anticipation. What we celebrate as having happened in the past points to what we anticipate is coming again.