But as it is, he has appeared once for all at the end of the ages to put away sin by the sacrifice of himself. And just as it is appointed for man to die once, and after that comes judgment, so Christ, having been offered once to bear the sins of many, will appear a second time, not to deal with sin but to save those who are eagerly waiting for him.
There are only a few ways to answer the question. Perhaps history is a line – this is how many today think of it. A line starting in the shrouded mists of the past that stretches ever onward. Maybe, if you have a modernist's optimism, the line trends upward – it is the “march of progress,” the direction of history that politicians like to cite – a direction always flowing curiously toward their positions. Maybe, if you're more cynical, the line trends downward – the past is a golden age of great men and women whose like we shall never know again. But the important thing is how unremarkable any specific moment is on that line. This time is just one more step on the plodding road of eternity.
Perhaps, instead, history is a cycle. This was the view of many of the ancients. Time moves like a grinding wheel; there are seasons of birth, of growth, of decay and death. Human existence moves like the seasons, spring fading into summer with the threat of winter inevitably on the horizon. But just like the line, the view of history as a circle also makes any specific moment unremarkable. We have been here before, and we will be here again.
What makes the Christian view of history striking is that it is neither a line nor a circle. Instead, Chrsitianity says, history is a story. It has the shape of a novel or a fairy tale, with building conflict and climaxes and resolutions. In this view, certain moments are remarkable. They move the story from one act into the next. There are conflicts and plot twists on which everything else hinges.
Advent is the time when we celebrate two of the greatest plot twists in this story, one in the past and one still to come. These two twists are Christ's two appearings.
The author of Hebrews recognized these two events. “At the end of the ages,” the author says, “[Jesus] has appeared. (Hebrews 9:26)” This doesn't mean the end of all history, but it does mean the end of what came before. Jesus is born, and everything before His coming was the first act of a play. Now, the scene is forever altered by His “sacrifice of Himself.” In His death, Jesus rewrote the script. The second act, where we now live, is about the outworking of an incarnate crucified Savior who rose again as the first curtain fell.
So we live in the age after Christ's first appearing, and Advent is a time to remember and celebrate that. But it is also a time to anticipate and prepare for the second twist: that “Christ, having been offered once to bear the sins of many, will appear a second time, not to deal with sin but to save those who are eagerly waiting for him.” (Hebrews 9:28)
Sometimes, when the tension of a novel is too much to bear, I flip ahead and read the last pages. There are those who might gasp in horror at such an admission, but sometimes I need it. I need to know how the story ends if I am going to endure the journey to get there.
In Christianity, we have such knowledge. We are rooted in this past event, but we are also moving toward a future event which, while not yet realized, is just as sure. Jesus Christ will come again. The salvation that began two thousand years ago in Bethlehem will be brought to completion. Our bodies will be resurrected and creation restored and justice dealt and the battle won.
We live as people not on an endless road or perpetual cycle, where every moment is basically the same as the last. We live as people who find the present defined by these two particular moments – a people between two appearings. At Advent, we seek to remind ourselves of those two moments and how they redefine our lives today.
King of kings, yet born of Mary,
As of old on earth He stood,
Lord of lords, in human vesture,
In the body and the blood;
He will give to all the faithful
His own self for heav’nly food.
Rank on rank the host of heaven
Spreads its vanguard on the way,
As the Light of light descendeth
From the realms of endless day,
That the pow’rs of hell may vanish
As the darkness clears away.