Some scholars have asserted that this parodying, or recycling of material, constituted laziness on Bach’s part. I do not believe this to be so. In fact, the re-using and re-arranging of existing material was common practice amongst composers at this time. Handel reused a significant amount of his operatic and instrumental music in different ways, as did other composers of the day. (After Handel ultimately failed as an operatic composer in the mid-1730s he turned to oratorio as a vehicle for composition. He was known to be a fast worker. This in no small part was due to his use of parody. Much of Israel in Egypt is parodied from his earlier operatic efforts, and numerous operatic love arias turn up as re-worked sacred commentaries in Messiah.) Parody mass settings were very common in the renaissance period, and examples can be found in the works of Palestrina, Dufay and Tavener, amongst others. In any case, it was not in Bach’s Lutheran nature to waste material, as is plainly evident from the surviving autograph score of the Christmas Oratorio, where not one single line is left blank. Since the composer’s frugality extended to his use of manuscript paper, a precious and expensive resource, it is scarcely surprising that complex, difficult and labour-intensive music would not have been discarded either. Bear in mind that this music had been written for a one-time event, and heard only once by a handful of invited guests and dignitaries, the equivalent of today’s politicians and minor royalty, who may not even have recognised its quality. In 1733 Bach had already parodied some earlier music to create the Kyrie and Gloria of his Mass in B Minor. Bearing in mind also C.P.E Bach’s record of his father’s prolific cantata output, it should not come as a surprise that, like his contemporaries, Bach recycled some of his material. 

However, not all of the music in the Christmas Oratorio is parodied. All of the recitatives are brand new, as is the music for the Evangelist, one or two of the more tender arias, and the instrumental sinfonia which opens Part 2. In the newly harmonised chorale melodies, Bach demonstrates his ability to challenge his own conventionalities. The chorale settings contain a new level of harmonic sophistication with complex tonal shifts and extended chromatic progressions leading to an even more piquant immediacy of expression and clarity of text than Bach had achieved in the Passions. If we trace the sequence of several hundred chorale settings from the earliest Leipzig cantata cycles of 1723 we see a line of development which culminates in these settings written for the Christmas Oratorio.

Nicholas Kenyon, in his detailed and scholarly modern biography of Bach, writes … “There is no more life-giving, joy-enhancing experience in Bach’s larger scale music than a great performance of the Christmas Oratorio.” He goes on to discuss the parodying of earlier works.  “In the 1730s the pressure for the weekly composition of a cantata for the forthcoming Sunday receded and, with it, Bach’s approach to composition changed into one of compiling single works into cycles and larger single compositions. (The six motets were written mostly between 1730 and 1737.) The Christmas Oratorio is a successful product of that change.”  The Lutheran church did not require “figured” (complex) music during the penitential season of Advent, and it is likely that this afforded Bach a window of time at the end of 1734 to create the Christmas Oratorio. The Easter Oratorio and Ascension Oratorio, written a few months later, were also largely parodied from earlier music. 

At the time of its creation, we know that Bach was becoming dissatisfied and disillusioned with his lot in Leipzig. In 1733 he had written a letter to Georg Erdmann, Kapellmeister in the then German seaport of Danzig (today known as  Gdańsk and now in the territory of Poland). The full text of the letter appears in Wolff’s book. It is a revealing letter, clearly written by a frustrated man, who complains about the excessive cost of living in Leipzig, and the fact that his salary is partly made up of fees from extra services. Noting that the number of funerals in Leipzig was significantly lower in this year, and so therefore was his income, Bach appears actively to be seeking alternative employment as he writes: “the authorities are odd and little interested in music, so that I must live amongst continual vexation, envy and persecution; accordingly I shall be forced, with God’s help, to seek my fortune elsewhere. Should your Honor know or find a suitable post in your city for an old and faithful servant, I beg you most humbly to put in a most gracious word of recommendation for me.” We know that this came to nothing and Bach, despite his disillusionment, saw out the rest of his days in Leipzig.