We begin today a traversal of the six cantatas known as the Christmas Oratorio. All six include much music that Bach had originally written for secular cantatas. The opening chorus of this work, for instance, began with the words "Tune the drums." Bach's transformation of this material to wonderful and idiomatic Christmas music is a marvel.The opening chorus begins with the drums and is followed up by a mighty rush with the strings and winds to the dazzling entrance of the trumpets. While in cantata format, the Oratorio includes a tenor Evangelist who narrates the story. This narration is in the form of recitative rather like those in the Matthew and John Passions. In order to keep clear what is narrative and what is commentary, all the recitatives have obbligato instruments. An alto recitative with oboes d'amore leads us into the familiar aria "Bereite dich, Zion." After the Passion chorale, which, curiously enough, begins and ends the Oratorio, the Evangelist continues. An interesting movement with the sopranos singing the chorale "Gelobet seist du, Jesu Christ" and a bass soloist singing a recitative underneath, leads us into the great bass aria "Großer Herr, o starker König." This work was originally in praise of the king, but its kingly trumpet part is totally suited to the new text. A wonderful and grand setting of "Vom Himmel hoch, da komm ich her" with the trumpets ends the cantata.