There are so many reasons Christmas should have lost its significance: "The lovely old carols played and replayed till their effect is like a dentist's drill or a jack hammer, the bathetic banalities of the pulpit and the chilling commercialism of almost everything else, people spending money they can't afford on presents you neither need nor want... Yet for all our efforts, we've never quite managed to ruin it" (Frederick Buechner, ‘Whistling in the Dark').

It may be the fact Christmas continues to have any meaning is something of a miracle in itself and testimony to the grand miracle lying at its core. That miracle can be summed up in a single word: Incarnation. It is a miracle and mystery beyond our understanding.

However, every year we are asked, again, to imagine what the "first Christmas" must have been like. To help us in this process we are met with a group of children with tea towels on their heads in a cardboard stable with bales of hay strewn across the front of the church. It is hardly an appropriate re-creation of "the central event in the history of the Earth" (C.S. Lewis, Miracles).

Yet somehow - and almost incidentally - it can begin to work. In the frailty of the expression, we may catch just a glimpse of the feebleness of this eternal moment.

Only in our retellings does the world stop for this moment. The town was crowded: the local residents and businesses were busy housing and feeding the influx of visitors; the out-of-towners were intent on either rest or revelry, letting off steam after a journey made under captive compulsion. It was probably not a silent night and any attending holiness would have been largely unappreciated. Only a small number of people in town that night even knew of His birth; fewer still had any clue as to its significance.

With most births and birthplaces, importance is usually only attributed with the benefits of hindsight, based on what that person grew up to achieve. Then, the circumstances of their birth and their birthplace may come to be regarded as noteworthy. However, if Jesus had done nothing other than be born, we still would be faced with an event of unfathomable mystery. That God could somehow become human... and that He would choose to...

Only in retrospect John could say, "We have seen his glory" (John 1:14), but in that long-ago stable, the largely ignored birth - now almost forgotten, in the mountains of tinsel, plastic Christmas trees and other Christmas junk - already dwelt "the fullness of grace and truth" (John 1:14).

In the sentimental overload of Christmas stories retold, we must never forget this miracle baby was born to die. From the moment of the earliest conception of the plan of incarnation the end result was to be crucifixion. We can marvel at the miracle beyond comprehension and a sacrifice in God stepping down so low as to become human. Yet it is only the starting point for the ultimate sacrifice of His death. It is the darkness of that moment 30-something years later that is the source of our true hope. It was this powerful light flickering weakly in the first cries of the baby-God: "In him was life, and that life was the light of men" (John 1:4).

From the darkness of that earthly night, that feeble light shines far brighter than the gentle lantern light in a carefully ordered stable or even the angel glow depicted on the Christmas cards. From that night, a light shines in the darkness of ourselves, our world, our despair and hopelessness - "but the darkness has not understood it" (John 1:5).

That which we do not understand is not particularly comfortable and, amid the tackiness, artificiality and stylised good will of the present Christmas, we still so clearly have not understood it - but that Light continues to shine its piercing beam into our darkness. God became light in the hope of being understood by the darkness. It is the central miracle of incarnation. As Frederick Buechner describes it, "It is not tame. It is not touching. It is not beautiful. It is uninhabitable terror. It is unthinkable darkness riven with unbearable light."