At the end of this volume are the variations in canon form upon the Christmas hymn Vom Himmel hoch da komm' ich her.[141] The combinations in which Bach involves this chorale melody, already often treated by him, might well dismay a contrapuntist; we wish to note here only that original melodic richness, often touching, under which is concealed such arduous labor leading to inconceivable results. Fatigued in following their intricacy, powerless to unravel the inextricable network, the mind clings to these threads, though still indefinite—music now superhuman in the swishing of invisible wings as they fold, or rustle like silk in their contact;—or gliding, rather, without conjuring up any special sound, but leaving to the fancy the whole halo of harmonies; or like an echo, as if fragments caught here and there repeated the song which spirit-voices pray—the white souls of the pure in heart—these voices in peaceful chords, strangely sustained, or so gently persistent that the saints must hear them, in ecstasies which one feels as in a dream; the song which the stars revealed, murmured to the Child, who was lulled by the incommensurable rhythm of the universal concert emanating from God.[142]
III
The Third Part of the Clavierübung contains twenty-one arrangements of chorales.[143] The "Hymns of the Catechism" and the Creed furnish twelve of them, each melody treated twice, with or without pedal. These chorales may be cited as examples of certain well-defined types; it is unnecessary to identify each one of them separately, rather will we leave to the reader the task of such a classification. Some of them, however, are deserving of special mention; the Vater unser im Himmelreich (treated in canon), for its extended proportions, for the fulness of its harmony; the Aus tiefer Noth (de Profundis) in six parts, with double pedal, noteworthy in that it appears to have been written for two pedal-keyboards of different intensity, the melody dominating by its power, crying out amidst the symbolical chaos of this gigantic polyphony.
We shall not again touch on that faculty which Bach possessed of translating into music the words of the chorales, whether in their most obscure meaning, or in their most obviously picturesque significance. Ein' feste Burg ist unser Gott, "A mighty fortress is our God," sings Luther, and Bach emphasizes the suggestion of impregnability by supporting the melody upon the deepest basses of the organ; but this firmness reveals itself only after the repulse of an attack, after the warring of the counterpoints below the ramparts.
It is the same procedure as in the Reformation Cantata Und wenn die Welt voll Teufel wär', "And were the world of devils full," as Luther's song runs; "on a sudden, figures of infernal aspect, issuing from unknown depths, rush to the assault upon the noble melody of the chorale."[144]
But such agencies partake rather of an instrumental style, interesting in an organ prelude, where they are more in place; in the cantata these counterpoints are entrusted to a bass voice; while putting the singer out of breath, they impress upon the audience a sort of wearisome anxiety; "without doubt," says Hanslick, "Bach obeys a fine symbolic instinct in entrusting the calm and steadfast melody of the chorale to one voice, while the other, in elaborate design, creeps about it; but not everything of symbolic significance must, for that reason, be beautiful in itself."
It is known that the last work of Bach was a chorale-prelude upon the melody of Wenn wir in höchsten Nöthen sein, or Vor deinen Thron trete ich,[145] which he dictated upon his deathbed to his son-in-law, Altnikol. This composition was added to the plates of Die Kunst der Fuge (the Art of Fugue), unfortunately lost, which Bach had had prepared at the time.
"To replace the unfinished portion of the last fugue, the work has for a supplement a four-part chorale, Wenn wir in höchsten Nöthen sein, which Bach dedicated some days before his death to his son-in-law, Altnikol. I will not dwell on the art which he displays here, for the profound science of music had been so mastered by the author that he could exercise it even in illness; but the expression of pious resignation and devotion with which it overflows has touched me deeply every time I have played it; and I cannot say which I would rather do without, this chorale, or the ending of the fugue."[146]