Did any other composer so thoroughly and systematically
summarize their entire compositional endeavor as Bach did in his later
years? In all the important fields in which he had worked he presents
a final chapter, bringing together and extending his research: in solo
performance the Goldberg Variations, a fascinating extension
of the old ground bass or passacaglia principle; in chamber music, the
cornucopia of The Musical Offering – canon, fugue, sonata,
running the gamut from the esoteric to the ingratiating. For his first
love, the organ, his orchestra under two hands and feet, he creates
Klavierübung Book III, with its Organ Mass, a heaven-scaling
encounter with the Luther catechism chorales. Later on arrives an even
more concentrated meditation on a Luther melody, the canonic variations
on Von Himmel Hoch. Finally, the assemblage of many years,
the monumental Art of the Fugue, simultaneously a marvel of
technical intricacies and the most colorful, varied, and spontaneous
collection imaginable. Common to all these: variation upon some given
material. Chorale melody, or something standing in for chorale melody,
stands as reference point for this music. Since his earliest pieces,
a dramatic and clarifying encounter between Strict and Free is his premise.
As Bach takes stock in 1748, only two years before his death, one central area is missing: the grand concord of voices and instruments which was at the center of his enterprise for long stretches of his career. In earlier times he had assembled many of the elements of a grandly-scaled Mass, a compendium of movements adapted from cantatas, interwoven with freshly composed material. But a very large segment was missing, the whole of the Symbolum Nicenum.
This Credo contains the texts most crucial to Lutheran theology: “I believe in one God,” and “We confess one baptism.” These Bach decided to compose fresh, finding and recasting the other mass sections from earlier cantata movements.
Anchoring these movements, no Lutheran chorale tune
about God as a mighty fortress (BWV 80), or Christ coming to be baptized
in the river Jordan (BWV 7). Instead we have the ancient Gregorian cantus
firmus. The Credo movement is a version of sixteenth-century
polyphony as radical as Beethoven’s modal music in the slow movement
of his String Quartet Op. 132. The anchorless, ubiquitous chant melody
shapes a ruthlessly abstract sound picture, the walking bass only seems
to make harmonic sense of a piece whose sense is not harmonic. The “I
believe” becomes a new Statute, a justification by faith alone.
The Confiteor, though brief, is made the goal point of the entire Mass. The thematic profiles are drawn like North German woodcuts, the polyphony is compact and eventful. Just when every permutation seems to have been displayed the old baptismal cantus enters. From this point on the piece takes on a hallucinatory quality, the cantus stamping out its bold shape, the original theme continuing gliding forward in a trance, leading into one of those passages found only in the greatest composers’ work. The writer is given (or gives) a sudden image of the future, in this case a kind of gliding, improvisatory modulation, soon the colorful province of Mozart, Schubert, Wagner and beyond.
The setting of Et expecto resurrectionem would be a perfect way for Bach to end his career as a vocal music composer, but there will be one more extraordinary piece. In its first completed form the et incarnatus est text concludes the duet Et in unum. Bach in his last weeks decided to give this text its own short movement, re-texting the duet to leave those words available.
This “Swansong” is fittingly a wonderful composition in a more esoteric sense than the Confiteor. Et incarnatus begins with all five choral voices imitating a downward motive. This is a familiar gesture. But Bach sends with this piece a coded message to one of his constituencies, the students-professionals-connoisseurs. The downward pealing imitations have the same general contour, but every one of them always has slightly varied intervals, that is, they sing the same tune, but never truly the same tune. Thus he vouchsafes to future generations a subtle new variation idea: melody defined more by shape than detail. This fertile notion has become especially useful to composers of the present time.
Bach must have been very satisfied to lay in this Et incarnatus next to the earliest music in the piece, the Crucifixus, adapted from Cantata 12 (1714). The two pieces collaborate, the thirty-five years between them drop away. Et incarnatus is calculated for its role in the continuity – it allows Bach to place two ostinati (repeated accompaniment patterns) next to each other, two pieces in which the chorus is distinctly foregrounded, two pieces transparent in texture, mysterious in content. Et incarnatus has the restraint and subtlety of a true Last Word, the harmonic changes logical but not predictable, its final phrase reaching an intimacy and universality of expression available only to a composer with nothing to prove.