Chapter 29 BWV 121 Christum wir sollen loben schon

We should offer praise to Christ.

Chorus/fantasia--aria (tenor)--recit (alto)--aria (bass)--recit (sop)--chorale.

The twenty-eighth cantata of the cycle for the second day of Christmas.


A compact and unostentatious cantata for this important day. The text praises Christ, and marvels at the Virgin Birth and the miracle of our consequent salvation. Additionally, and unsurprisingly, it takes the opportunity of reminding us of our own human inadequacy.

Students should compare Cs 91, 121 and 133, written for the first, second and third days of Christmas 1724 with the equivalent works from the first Leipzig cycle, Cs 63, 40 and 64 and the cantatas of the Christmas Oratorio. In particular they should compare and contrast Cs 121, 40, and 248/2, all conceived for this second day.

C 40 was the first of Bach's Leipzig cantatas to be written for this occasion and is a very different work from C 121. Its theme is that of Satan, the bringer of sin, and Christ's victory over him. Bach interpolated two chorales in each of C 40 and 64, presumably already in the repertoires of the choir, but if not, capable of being performed at sight. One must remember that at this festive time of the Christian year the Magnificat and three cantatas were performed in as many days. If we include the New Year celebrations, we find that five cantatas and the Magnificat were performed in a mere eight days, a considerable feat for the most professional and experienced of choirs, even today! So it is not surprising that Bach reduced the load of learning new music wherever possible.

No quarter had been given in the opening chorus of C 40 however. There we find a movement which sets out as an Italian ritornello but develops into a giant chorale prelude-cum-fugue in four parts. Both cantatas contain bass arias but otherwise they are quite dissimilar. That from C 40 describes, to the sounds of chopping and slithering strings, the hacking of the serpent′s head. This is Bach's dramatic music at its most extrovert, an example of the operatic rage aria that he had actually been forbidden to write by the conservative ecclesiastical authorities at Leipzig.

The bass aria from this cantata is, as we shall see, positively joyous.


The chorale of C 121 is oddly archaic and inevitably dictates the characteristics of the opening fantasia. Boyd (p 101) declares its origins to be in the fifth century and its Phrygian modal implications are clear (see also that of C 38, chapter 22). Dürr (p 112) suggests that the mixed modes would have made the melody seem antiquated even in Bach′s day.

Bach's harmonization is something of a hybrid affair as he attempts to force it into a more contemporary tonal mould, beginning in E minor and passing through D and G majors to end on an imperfect cadence in B minor! It may be that some will feel that this is not one of his most successful harmonisations!

But the effect, with cornet, trombones and strings doubling the four choral lines is certainly archaic and it may well be that it is this sense of historical perspective that Bach sought to evoke.


And if this was his intention, we can certainly detect it in both the technique and disposition of the opening fantasia. We will find no modern French Overture or Italian concerto styles here! This is a severe, though highly fluid, traditional motet of the kind to be found in Cs 2 and 38 (chapters 3 and 22). There is no independent orchestral writing apart from some sections of the continuo line. Strings and trombones simply double the lower voices with cornet, first violins and oboes d'amore supporting the sopranos. Once again, the sound is oddly medieval although the richness of the four-part fugal writing is distinctly Baroque.

The text is a simple hymn of praise to the Son of the Virgin; praise which must radiate, like the sun's rays, to all parts of the earth. One would imagine a strong sense of joyousness in the communication of this message but it is certainly not of the same order that we find in the more contemporary sounding fantasias placed on either side of this work, Cs 91 and 133. This movement conveys a restrained sense of pleasurable satisfaction, set within the context of a long historic tradition. There is an underlying feeling of gravity about this message.

Each chorale phrase is introduced by fugal expositions of itself in the lower voices. The long notes of the chorale melody emerge and shine through the complex counterpoint and the voluminous praises radiate out in all directions. The final extended cadence is formed from the lower voices swirling below a note of f# sung by the sopranos and held for eleven bars! The symbolism could not be clearer as the melismas in all parts carry forth the single word----reicht---earth, world, empire, dominion, all lit by the glow of acclamation.

But the movement is not without structural challenges, created mainly by the squeezing of a melody from one tradition into that of another. The key scheme of the fantasia largely follows that of the chorale described above, Em, D, G and Bm. The key signature is two sharps, that of the key in which it ends rather than begins. This in itself is indicative of Bach's technical problems. It is very rare for a large-scale Baroque movement to begin and end in different keys and the fact that Bach does so is indicative of his willingness, on this occasion, to allow aspects of archaic style to override contemporary harmonic practice.

Further discussion of this issue of keys used to begin and end movements may be found in the analysis of the last movement of C 68 (chapter 49).

Tenor aria.

B minor, now established, is retained as the key for the substantial tenor aria that follows. Schweitzer (vol 2, p 358) again rants against the 'barbarous declamation' and offers the opinion that 'it is incomprehensible how Bach could listen to it'. Today we may view the movement rather differently.

Clearly Bach seems comfortable returning to a contemporary style; in most ways this is a conventional Italian da capo/ritornello movement. However, the tonal experimentation of the first movement seems to have intrigued him for he has not entirely abandoned it. The oboe ritornello begins in, and firmly establishes, B minor. But it moves to, and cadences in, D major at the voice′s point of entry! It may be that Bach is suggesting the marvel of revelation revealed in the text----do not attempt to understand; simply wonder at the way God has raised wicked and unworthy mankind to salvation. Movement from minor to major may well be intended to symbolise that process of evolution to higher things.

In fact the aria, whilst predominantly minor in mode, contains numerous flashes of major appearing, sometimes, almost without warning. This may be suggestive of the contrasts between man the lowly and God on high; it may also hint at man's negligible insights into God's unfathomable plans. It is possible that the combination of three and two-bar phrases, evident from the beginning in the structure of the ritornello theme, has similar metaphorical meaning for Bach.

          Opening 3-bar phrase, followed later by one of 2-bars.

The stressing of the word retten---to save----on five successive melismas in the middle section, makes its point without ambiguity; Man, so mean and lowly when compared to God, may still be saved from damnation.

Alto recitative.

The alto recitative simply reminds us of the miracle of infusing the pure soul with grace as God now turns his attention towards mankind. Both Boyd (p 101) and Dürr (p 113) note the extraordinarily sudden twist of harmony in the last two bars. The modulation is effected between two highly unrelated keys, F#m, in which the recitative begins, and C major, that of the following bass aria.

Bach often contrives to bring his recitatives to a close in the key of, and as a preparation for, the next movement although he usually does it more subtly than this. Here we have a powerful and dramatically unexpected wrenching of the harmony, something which, in other circumstances might appear clumsy and amateurish. Clearly Bach's purpose here is less structural than imagic. Suddenly and dramatically our attention is drawn to God's turning towards, and fixing his favour upon us. We had only glimpses of this in the tenor aria; now it is forced upon our attention and we, like John the Baptist, must both heed and rejoice.

Bass aria.

Yet again, we find that the last aria is the longest and the most revealing of the entire cantata. The mood is now triumphantly major. The wondrous themes of the Virgin Birth and God's plan for our salvation may be beyond our intellectual understanding, poor creatures that we are; this has been made quite clear in the preceding movements. But a deficiency of understanding does not preclude celebration and so rejoicing is what we are now exhorted to do. John showed by his joyous bounds that he recognized Jesus as, indeed, should we. Furthermore, Christ's actions have enabled us to seek to leave this troubled world with clear consciences and join Him in His haven of peace.

           Opening ritornello theme.

There is clearly more than a touch of old-fashioned pedagogy here; do not question or seek to understand, just do it!

The scale and tonal planning are both points worthy of comment; in a sense this is three movements in one. The long string ritornello, which will be heard four times unaltered is, in itself, a complete miniature binary form movement. Beginning in C, it cadences in the dominant G and returns to C for the voice entry. Had this been presented as a short keyboard piece in two parts it would have sounded structurally complete and perfectly satisfying in itself. It contains, however, a wealth of different musical ideas, somewhat unusual for Bach the great developer of the individual motive. Perhaps, by means of this musical lavishness, Bach is suggesting the unlimited abundance of treasures that may be discovered in the arms of the Lord!

The ritornello frames the first vocal section, itself structurally cohesive and similarly dominated by the major keys C and G. There are no shadows or sorrows here. Again, the piece could have ended without an extended B section without any feeling of structural imbalance;

But there is more to come; a middle section (beginning bar 71) will take us to quite a different level. We have had the extrovert physical leaps of unalloyed joy; now it is time to consider the matter a little more seriously.

The text relates the Christian desire to leave this world and unite with the Saviour. This is a more complex message involving natural feelings of loss and bereavement with suggestions of salvation and deliverance. The keys are now minor, the mood more serious and the first violin lines, at times, quite convoluted. Here is a much more intricate set of emotions reflecting the complexity of the human condition; even if we trust in God and believe in His Grace, we must still go through the process of our own deaths and suffer those of others. The convoluted melisma on Welt----the world---- simply emphasises the universality of the situation (bars 96-8).

Knowing what we do of Bach's own personal life, these thoughts may well have touched a profound chord in him.

But the middle section returns to, and ends in, the major key and the traditional da capo aria concludes with an unaltered recapitulation of the first section. Bach has made use of an entirely conventional process in order to emphasise the universality of the experience.

Soprano recitative.

The final soprano recitative also touches lightly upon the complexities of the human condition. It stretches the singer's range beyond its normal upper limits and particular melodic emphasis is given to important words seufzt----sigh---- and----unermesslich----immeasurable or infinite, and finally jauchzend----a cry of joy, literally articulated as the singer strives towards a top b natural.

But the ultimate message of the movement is positive and simple; He did it for us and consequently we offer Him praise and thanks.


The final B major chord of the recitative leads us neatly back to the archaic chorale. Its text dispenses with all complexity and simply affirms our praise and gratitude for the Divine Family: God, Jesus, the Virgin and the Holy Ghost.

The main messages of this cantata concern simplicity and gratitude. But Bach has also allowed us to muse upon some of the emotional complexities embracing the core and nature of humanity.

Muse upon yes, but perhaps we should not allow ourselves to become obsessed with them!


Copyright: J Mincham 2010.   Revised 2012 and 2014.
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