Advent is the liturgical season when Catholics spiritually prepare for Christ's three comings, or advents: first, His past coming as a babe and sacrificial savior; second, His future coming as judge; and third, His present coming as eucharistic Lord.
Saint Bernard of Clairvaux speaks of Christ's threefold advent in his homily, which the Catholic Church places during Advent in Her Office of Readings. In his homily, this Doctor of the Church proclaims, "We know that there are three comings of the Lord. ... In His first coming, Our Lord came in our flesh and in our weakness; in this middle coming, He comes in spirit and in power; in the final coming, He will be seen in glory and majesty."
During Advent, which begins the Church's spiritual new year of grace, Catholics form spiritual resolutions to live more like and with Christ, whom they receive at Mass in Holy Communion. Priests wear purple vestments prior to Christmas to symbolize the spiritual house cleaning that Catholics are urged to accomplish at this time by penance, almsgiving and prayer.
Both the secular world and traditional Catholics celebrate Christmastide for 40 days. But the secular world starts the season right after Thanksgiving at so-called "Black Friday" and continues for 40 days until New Year's Day. Catholics, because they keep Advent, start celebrating Christmastide at the Christmas Vigil Mass and then continue for 40 days until Candlemass Day on Feb. 2. Candlemas Day incorporates both the Purification of the Mother of God and the Presentation in the Temple of her divine Child Jesus.
Spiritual resolutions are prayerfully formed by Catholics during the four weeks of prayer and contemplation of Advent leading up to Christmas. The secular world waits until after Christmas before thinking for a few days of what superficial resolutions they wish to make on Jan. 1.
Watch the panel discuss how the joy of Christmas depends on the season of preparation in The Download—Advent.