The Church has always had a different relationship to time than the world. She lives in the now and not yet of the Resurrection and Last Day. She hopes for her Savior to return in glory while suffering the constant assaults of sin, death, and Satan. One generation is born; another generation dies. Clans, tribes, and nations rise and fall. The world has its clocks and calendars to ensure that their time isn't wasted, but the Church waits.
For two thousand years, the Church has waited for her Lord to return. She is patient even as the world tries to leverage every second against the encroachment of decrepitude and death. That's why the Church is attacked, insulted, mocked, cursed, and persecuted. To a world enslaved to time (because it has no future), the Church's disregard for clocks and calendars is ridiculous. The Church's hope is the coming of her Lord, Jesus Christ, who daily strengthens and encourages us through his word and gifts of salvation.
People put their hope in the old world of the law, sin, and death. They don't care about the purpose of Advent or the true meaning of Christmas. They have their traditions, myths, and feel-good stories about Christmas that wash-out and wash away the double meaning of Advent and Christmas.
The Church is always in Advent, and every Christian constantly lives in Advent
That's why the Church will never be able to win over the world. The apocalyptic proclamation of the Lamb of God, who's born for the rising and falling of many, doesn't fit into most peoples' worldview. Most people imagine Christmas can be a time of "peace on earth and goodwill toward men" apart from the Christ-child. But that's because they haven't heard the preaching of Advent.
That is what our God calls us to today, as he always has called his Church to announce the coming of the Lamb of God, crucified from the foundation of the world. The Church is always in Advent, and every Christian constantly lives in Advent because we hope for the coming of our Lord in judgment.
We are called to testify to the history-shattering truth of God's birth. We preach, pray, sing, and witness to it. Even as the world refuses to hear what we have to proclaim, we carry on speaking the truth of Advent: "Blessed is he who comes in the Name of the Lord!"
We confess that "Jesus Christ, true God, begotten of the Father from eternity, and also true man, born of the Virgin Mary, is my Lord, who has redeemed me, a lost and condemned person" (The Small Catechism, 2nd Article of the Creed)
This is the Advent message of God that transcends the generations, calling all sinners to repent and believe because the day of the Lord is at hand. For the Church, then, it's always Advent. It's always a time of hope and affliction, sin and grace, law and gospel, the now and not yet of our apocalyptic faith.
In spite of disappointment and doubt, we are strengthened by the word which announces, "I will never leave you or forsake you." This is the mystery of God's birth. The mystery that the Church proclaims, that our God became a man, sacrificed himself to us, and was raised from the dead for our justification. It is the mystery of the One who comes to us hidden under the means of the Spirit in the Lord's Supper. This is the mystery of Christ's coming that is the Church's one, sure hope. That is why the Church in every generation exclaims, "Come, Lord Jesus!" And he says, "Yes, I am coming soon."