With a text from Revelations 12:10, this spectacular one-movement cantata is scored for double choir, and an impressive, military band-timbred instrumental ensemble consisting of three oboes, three trumpets, tympani, string orchestra, organ, and cembalo.
The work opens with a strong declaration in unharmonized octaves between the bass voices of Choir I and the lower strings. Creating a feeling of rising excitement, the important words are emphasized on strong beats, each one higher in pitch than the previous: (on D) Nun ist das (F sharp) Heil (D) und die (G) Kraft (D) und das (A) Reich (D) und die (upper D) Macht unsers...[Now has salvation and strength and the kingdom and the might of our...].
After this steady succession of three even beats (3/4 meter) to a measure, Bach makes a curious and thrilling rhythmic change in the melody by a series of 2 + 2 + 2 beats (as if in 2/4 meter) filling two measures on the words "...Got-tes sein-es Chri-stus (worden)" [God appeared in his Christ] which gives the beat a floating, turn-around feeling, as in some folk dances. Some interpreters, however, prefer to de-emphasize this wonderful shift by excessive legato playing of this passage.
The Choir I tenors enter with the theme a fifth higher, in fugal imitation style, while the basses continue with the text "...for now is cast down the one who accused them (the brethren) day and night before God" which is set to quick vocal arpeggios (in eighth notes) and skipping figurations (in sixteenth notes). The altos and sopranos of Choir I enter on the previous bass and tenor tones creating a clear and fluid four-part counterpoint in a full Italian style.
Suddenly Choir II enters with a descending version of the theme in full harmony on steady beats while Choir I, doubled by the strings, is engaged in complex rhythmic counterpoint with various single voices sustaining long tones as pedal points. The first and second parts of the text are sung simultaneously. Adding to this texture, a trumpet plays the original ascending theme and the three oboes play fanfares that quickly ascend in flashes. The combination of all these parts is rich and overwhelming.
The first important modulation begins as Choir I is again isolated, accompanied by the three oboes which alternate between fanfares and doubling the choir. The choirs are then treated in an arresting call-and-response manner, employing short textual phrases.
Bach then creates a marvelous symmetry midway through by accumulating voices from the sopranos downward, an inverse of the beginning procedure. The previous call-and-response passage between the two choirs is briefly evoked with trumpet-like tattoos played alternately by the upper strings, three oboes, and three trumpets.
The last 12 measures depart radically from the basic tonalities heard up to this point as radical chromatic writing indicates that some plateau has been reached and it's time to close.