The word “advent” means “coming.” As the first season of the church year, Advent marks the coming of Jesus, both his first coming in the Incarnation and his second coming at the fulfillment of God's purpose. The Gospel readings for Advent focus on John the Baptist, the herald of Jesus' coming, and on his mother Mary, the bearer of his coming.

Advent is a penitential season, meaning it is a time for confessing one's sins and sitting with God. In the early years, Advent was a 40-day season of preparation for baptism, much like Lent. Baptisms were performed on the Feast of the Epiphany (January 6). When Christmas Day (December 25) became the more prominent holiday, Advent became a four-week prelude to Christmas. During Advent, churches that use altar hangings and clergy vestments will use the color purple (as is the case during Lent), or, if available, a dark blue.

Many churches and families use an “Advent wreath” to mark the four Sundays of Advent. These sets typically have purple candles for the first, second and fourth Sundays, and a pink or rose candle for the third Sunday, known as “Gaudete Sunday” (from the Latin word “Rejoice”), when tradition allowed an easing of the Advent fast.

Popular Advent hymns emphasize the theme of coming. “O Come, O Come, Emmanuel” and “Come Thou, Long-Expected Jesus” are two examples.

The arrival of Advent Sunday in late November or early December means the start of a new cycle in the lectionary of assigned readings. Most liturgical churches use a three-year cycle (Years A, B and C), each focused on a different Gospel.