Advent - a time to REMEMBER our Christian history! A time to remember that the greatest hope and the fulfillment of God's plan of salvation begin in a small stable! I think its fitting that the Lord came in such a small subtle dirty way. In a manger, there was hope and promise and faithfulness. God was emmanuel ("God with us") in unpleasent circumstances -- and He continues to provide hope, salvation and comfort in unpleasent circumstances!
"Advent is concerned with that very connection between memory and hope which is so necessary to man. Advent’s intention is to awaken the most profound and basic emotional memory within us, namely, the memory of the God who became a child. This is a healing memory; it brings hope. The purpose of the Church’s year is continually to rehearse her great history of memories, to awaken the heart’s memory so that it can discern the star of hope...It is the beautiful task of Advent to awaken in all of us memories of goodness and thus to open doors of hope."
Joseph Cardinal Ratzinger,
"It seems, then", said Tirian..."that the Stable seen from within and the Stable seen from without are two different places."
"Yes," said the Lord Digory. "Its inside is bigger than its outside."
"Yes," said Queen Lucy. "In our world too, a Stable once had something inside it that was bigger than our whole world."
CS Lewis, The Last Battle