When we reflect on such things, we shall simply no longer be able to divide history into ages of salvation and of iniquity. If we then extend our vision and look at what Christians (that is, those people we call 'redeemed') achieved in the world by way of iniquity and devastation, in our own century and the previous centuries, then we will be equally incapable of dividing the peoples of the world into those who are saved and those who are not. If we are honest, we will no longer be able to paint things black and white, dividing up both history and maps into zones of salvation and iniquity. History as a whole, and mankind as a whole, will appear to us rather as a mass of gray, in which time and again there appear flickers of that goodness which can never quite be extinguished, in which, time and again, men set out toward something better, but in which also, time and again, collapses occur into all the horrors of evil.
Yet when we reflect like this, it becomes plain that Advent is not (as might perhaps have been said in earlier ages) a sacred game of the liturgy, in which, so to speak, it leads us once more along the paths of the past, gives us once more a vivid picture of the way things once were, so that we may all the more joyfully and happily enjoy today's salvation. We should have to admit, rather, that Advent is not just a matter of remembrance and playing at what is past - Advent is our present, our reality: the Church is not just playing at something here; rather, she is referring us to something that also represents the reality of our Christian life. It is through the meaning of the season of Advent in the Church's year that she revives our awareness of this. She should make us face these facts, and make us admit the extend of being unredeemed, which is not something that lay over the world at one time, and perhaps somewhere still does, but is a fact in our own lives and in the midst of the Church.
Cardinal Ratzinger, What it Means to be a Christian (a book of Advent sermons)