There is a fad in some quarters about a "theology of incarnation," meaning that our task is to discern what God is doing in the world and to do it with him. But that is only half the truth, and the wrong half to start with. John's theology of the Incarnation is about God's Word coming as light into darkness, as a hammer that breaks the rock into pieces, as a fresh word of judgment and mercy. You might as well say that an incarnational missiology is about discovering what God is saying no to today and finding out how to say it with him. That was the lesson Barth and Bonhoeffer had to teach in Germany in the 1930s, and it's all too relevant as today's world becomes simultaneously more liberal and more totalitarian. This Christmas, get real, get Johannine, and listen again to the strange words spoken by the Word made flesh.
N. T. Wright, "What Is This Word?"