Bach Cantata BWV 40 Dazu ist erschienen der Sohn Gottes was composed for the second day of Christmas. The text is concerned with Jesus’ description of the rejection and persecution of the prophets, attendant to the story of the Stoning of St. Stephen as recounted in Acts. This accounts for the strange tone of the cantata BWV 40 that, even though it quotes the great passage at the beginning of the Gospel of John and makes other references to the birth of Jesus, is full of battle cries against the devil. The sole purpose and meaning of Christ’s birth, as seen here, is to do battle with the devil.
The opening chorus is a superb example of Bachian military music. Two horns, two oboes and the strings trade off a fanfare figure, that grows into a full-fledged battle cry. The chorus enters with blocky statements of the text. They eventually shout out the idea of the battle with the devil in regimented and disciplined rhythmic precision. Occasionally Bach will present texts in two contrasting ways. We see this startlingly in the bass aria of Cantata BWV 101, where each phrase of the chorale is set both slowly and in an agitated character. After the initial outward brilliance of the opening BWV 40, the chorus sings the same text as a rather lyrical and inward fugue at half the tempo of the previous material. The ultimate integration of this fugue with the previous material is a great tour de force of the first Jahrgang (cycle of Leipzig cantatas). The way that the counter-subject of the fugue subtly works itself back into the opening character is a marvel. There is something devilishly subversive about that theme. The fugue is very extended with a full return to the original battle music. The chorus is in a modified da capo form with a fugue as the B section, a distinctive and unique idea in the cantatas.
The secco tenor recitative begins with a pedal point as the singer intones the words, “the word was made flesh.” As surely as Mozart changes the scene in Figaro by little scale passages in the recitatives, Bach here sets off the quote from John by accompanying the commentary with an ascending scale passage in the continuo.
Four-voice chorale harmony usually stands in the cantatas as a pillar of congregational wisdom. Chorales almost always stand back from the action and often have a rather cool. Almost dignified, response to the more passionate recitatives and arias. There are three chorales in Cantata BWV 40. They have a folksy, almost rough, quality to them. The sophistication of the pervious material is reduced in the first chorale to “Sin makes sadness, Christ brings joy.” The words are superbly colored both by the marvelous ambiguity of the major/minor harmony and by the block-like chord presentation. The pithy little opening statements are followed by a marching tune accompanied by a descending eighth-note bass line. Compare this treatment to the elevated, almost angelic, presentation of this chorale tune at the end of another Christmas cantata, BWV 110.
The cantata then plunges into more devilish music. Here the serpent’s tail is portrayed by the twisting whiplashes of the first violins. The terse oboes and strings punctuate it almost brutally. The aria is marvelously grotesque. Notice how the misshapen voice line lurches almost drunkenly on top of the subversive bass. The snake turns from lashing dragon to sinuous serpent in the alto recitative. The alto line meanders languorously between the rolling strings figuration and the sparse bass. It is as secretive and inward as the aria was blustery and aggressive. The recitative is one of the few moments of quiet in the whole cantata, reminding us that this is the same serpent that brought down Adam and Eve.
The next chorale is even more folk-like than the first. Its blocky wisdom is in extreme contrast to the silky sophistication of the previous recitative. The ending passage into the realm of joy is one of the great moments in all of the chorales. Daring and complex wind writing, as seen here, separates Bach from all of his contemporaries. In the tenor aria that follows we have a major wind-band tour de force. Bravura oboes and horns accompany the virtuoso and high-flying tenor part. The melismas on the word “freuet” accompanied by dazzling horn and oboe fanfares give the aria an inimitable heroic flavor. There is an interesting sense that this passage is cut from the same cloth as both the serpent’s tail in the bass aria and the “work of the devil” in the opening chorus. The cantata could sound like a brilliant string of unrelated pieces if it didn’t have the underlying unity of similar musical material.
The final chorale “Freuet euch ihr Christen alle” begins similarly to “Jesu meine Freude.” Its deep seriousness gives the cantata a surprising close after the bravura of the tenor aria. This chorale has the same shape as the second chorale, with folk wisdom leading to a sublime and surprisingly profound conclusion. While not exactly unknown, this cantata is greater than is is usually given credit for. The progression of ideas and the unusual, even unique, way in which the chorales function make it sui generis in the literature.