Advent is a season of preparation that has a twofold purpose. Advent begins with Evening Prayer I of the Sunday falling on or closest to 30 November and ends before evening prayer I of Christmas. We prepare ourselves not only for the coming joy of our celebration of the birth of the Christ child; we also prepare ourselves for the Second Coming of Christ.
For Catholics, Advent is the beginning of the new liturgical year. We begin with Advent, awaiting the birth of Christ, then celebrate the Christmas Octave and season, Epiphany, and then soon begins Lent, in preparation for Easter. Then, after the Easter season ends with Pentecost, we have the bulk of Ordinary Time until the end of the liturgical year, and Advent again.
The readings at Mass reflect these times in the life of Christ. They take us through his birth, baptism, ministry, Passion, Death, and Resurrection.
Many Christian denominations celebrate Advent, perhaps in ways a little different from those of us who observe a liturgical calendar and cycle. But the focus, the point, is to prepare for the coming of Jesus.
https://www.baptistpress.com/resource-library/news/advent-rediscovered-by-southern-baptists/
We will have posts for each Sunday of Advent, beginning this weekend.