Perhaps you were expecting a purely historical account as one might give of the battle of Waterloo, whereas I was trying to treat it as a religious event which eternally recurs every time it is accepted. Thus the historical fact that the shepherds were shepherds is religiously accidental — the religious fact is that they were the poor and humble of this world for whom at this moment the historical expression is the city-proletariat, and so on with all the other figures. What we know of Herod, for instance, is that he was a Hellenised-Jew and a political ruler. Accordingly I have made him express the intellectual’s eternal objection to Christianity — that it replaces objectivity with subjectivity — and the politician’s eternal objection that it regards the state as having only a negative role. (See Marcus Aurelius.) …
I am not the first to treat the Christian data in this way, until the 18th Cent. it was always done, in the Mystery Plays for instance or any Italian paintings. It is only in the last two centuries that religion has been “humanized,” and therefore treated historically as something that happened a long time ago, hence the nursery prayer of Jesus in a nightgown and a Parsifal beard.
If a return to the older method now seems startling it is partly because of the acceleration in the rate of historical change due to industrialization — there is a far greater difference between the accidents of life in 1600 AD and in 1942 than between those of 30 AD and 1600.
From a letter W. H. Auden wrote to his father in October of 1942, explaining his decision to use a largely contemporary setting for his long poem For the Time Being: a Christmas Oratorio. I’m working on a critical edition of that poem for Princeton University Press, and goodness, it’s fun.