Of all of the von Ziegler texts, the one for BWV 128 “Auf Christi Himmelfahrt allein” is the most irritating. Here is a text so bumblingly conceived, and most importantly so anti musical that it almost defeats even Bach at the height of his powers. The readings for Ascension day are two complementary descriptions. In one, the very end of the Gospel according to Mark, the ascension is almost incidental to the exhortation to go into the world and preach the gospel. The very beginning of Acts has the more vivid picture, not only the one that is the source for the many paintings of the subject, but certainly an image that can be used in musical description of the story. The cantata begins strongly. The first chorus uses the great chorale tune “Allein Gott in der Höh sei Her” It appears with a different set of words, appropriate toe the Ascension.
The chorus begins wonderfully. Amidst fanfares from the winds, strings, and high horns in G.. The energetic theme emerges in the 2nd bar. It is treated imitatively among all the strings and oboes with the horns adding repeated notes and fanfares. The 1st horn finally plays the tune leading us into the chorus entrance. The melody is in bar form. The most striking thing about it is the Abgesang whose first two phrases are identical except that the second is pitched one step higher than the first. The last phrase of the Abgesang is a longer variant of the second phrase of the Stollen. The ratcheting up of the tension at the beginning of the Abgesang by raising pitch of the second phrase is useful compositionally and is a feature also of the many great organ chorale settings of this tune.
After a secco recitative, the bass aria sets up the first fatal flaw of von Ziegler’s text. It is a vision of the disciples seeing Jesus in heaven at the right hand of the father. Bach sets it up ingeniously with a big trumpet solo with strings. At the moment where the text announces that one day the sinner will one day go to where Jesus now lives, the aria literally floats away into a string recitative. The problem is that von Ziegler ends her aria text with a line, “ so hush, presumptuous mouth, and do not strive to fathom this mighty thing.” By completely undercutting this vivid scene by telling the narrator to be quiet breaks one of the cardinal rules. Never tell a singer to shut up. Bach rather limply ends the recitative and plays the opening trumpet and strings ritornello to end the aria.
The following duet has the same problem but magnified further. The last line of text in the A section says “My mouth falls dumb and still.” Since this line particularly in a da capo form is repeated over and over the result becomes almost comical. Richard Strauss parodies this kind of thing in Zerbinetta’s aria from “Ariadne auf Naxos.” Bach makes a valiant effort with the piece. There is a nice contrast with the opening phrase and the beginning of the b section.
In the first phrase the bottom drops out at the word “ergründen” In the beginning of the B section the same phrase takes off at the words “Ich sehe durch die Sterne.” Unfortunately the two voices have none of the psychological tension with each other that characterizes most Bach alto-tenor duets.
Rather the reprising “Allein Gott in der Höh sei Her,” Bach ends the cantata with a harmonization of “O Gott du frommer Gott,” with independent horn parts.