Whereas what passes for “advent” in the world around us (and often within) is the month-long shopping-season-frenzy that begins with Black Friday (or before), the Church’s holy and penitential Season of Advent begins with the Sunday closest to the Feast of St. Andrew (30 November).
Though it is somewhat coincidental that St. Andrew should thus mark, in a sense, the beginning of the Church Year, it is entirely appropriate that his festival day should serve in this way. He was the first of the Twelve to begin following Jesus as a disciple, as we hear in the Holy Gospel appointed for the Feast of St. Andrew (St. John 1:35-42). Significantly, he does so in response to the preaching and ministry of St. John the Baptist, who points to the Lord Jesus and declares Him to be “the Lamb of God” (St. John 1:35).
The first thing St. Andrew did, in turning from St. John the Baptist to follow after Jesus the Christ, was to get his brother, Simon Peter, and bring him along. And in this blessed work of bringing his brother to the Lord, St. Andrew was already anticipating the holy Office to which both he and Simon Peter would be called and ordained. Not only were they called to follow the Lord as disciples, but they were sent in His Name as Apostles to preach and to baptize, to catechize and care for the children of God. As such, they continued the ministry of St. John the Baptist and of Christ Jesus Himself, calling sinners to repentance and to faith in “the Lamb of God who takes away the sin of the world” (St. John 1:29).
To the close of the age, it is by that same apostolic ministry of the Gospel that Christ Jesus makes His Advent among us and so prepares us for His glorious Advent on the Day of Judgment.