Christmas Oratorio, Johann Sebastian Bach, BWV 248

   The most famous of Bach’s three oratorios, it is actually a set of six self-contained church cantatas linked by the birth narratives from the St. Luke and St. Matthew Gospels running through them all. Bach performed them during the six festival days of the Christmas season of 1734–1735: Christmas Day, St. Steven’s Day and Holy Innocents (26 and 27 December), Feast of the Circumcision (1 January), Sunday (2 January), and Epiphany (6 January).

   The text is set much as in Bach’s passions. The Gospel text is sung to tenor recitative, with speeches by the shepherds or another group given to through-composed "madrigal" choruses. Solo ariosos and arias comment upon the events. Each cantata begins with a substantial chorus introducing the day’s theme, except the second in which a sublime pastoral sinfonia sets the scene instead and concludes with an often highly elaborated summary chorale.

   Most of the concerted movements in the Christmas Oratorio are parodies of secular cantatas composed for the Elector of Saxony in 1733 and 1734. Each cantata has a different scoring, reflecting the theme of the day, so that for example the second day, setting the shepherd narrative, eschews the festival brass and requires only the "pastoral" colors of flutes, oboes d’amore, oboes da caccia, strings, and continuo. Performing the entire set requires in addition three trumpets, two horns, and timpani, and about two hours time. The choral parts, as in most of Bach’s works, are challenging.