Sonata-Principled Praises

Lent concludes during this month, and that means that many Easter performances of Beethoven's "Hallelujah," the popular chorus that concludes his unpopular oratorio Christ on the Mount of Olives, are just around the corner.

This is a rather unusual movement to bring up as an example of the sonata principle, because, as befitting a coda-chorus, it hardly strays from its main key of C major. In fact, it never provides an authentic cadence in any other key. The closest it comes to such a cadence, complete with a chromatic predominant and a 6/4 embellishment of the cadential dominant, is this:

If the sopranos had descended from E (A:^5) to A (A:^1) instead of ascended to G (enclosed in red above), then this would be a clear full close in A major. The G is both a surprise -- foiling a well-prepared escape from C major -- and not a surprise -- the A7 chord sends the music back, via a circle of fifths, to the movement's main key and tonic triad.

Toward the end of the movement, this happens:

If the basses had descended from G (C:^5) to C (C:^1) instead of ascended to B flat (enclosed in red above), then this would be a clear full close in C major. The B flat is both a (welcome) surprise -- foiling yet another authentic cadence in C major -- and not a surprise -- the lean toward the subdominant key is a common perorative technique in classical tonal music, and the basses's ascending-minor-third digression from the movement's main key recalls the soprano's earlier similar digression from a different key.