Here is an excellent article by Jon Pott titled "The Triumph of Genius: Celebrating Mozart." 2006 is the 250th anniversary of Mozart's birth. One brief excerpt in a long and helpful article:
Mozart has probably received more attention from theologians than any other composer save Bach. Most famously, there is Karl Barth, who began each day by listening to Mozart and found in him as he found in no other a transporting freedom and play within order, an affirmation "of a world which in sunlight and storm, by day and by night, is a good and ordered world." Barth is quite sure that in heaven, the angels, when left to their own devices, play Mozart, the good Lord listening in with special pleasure.