Harmony in Bach: O Jesulein süß

Jan 20

Non-chord tones help make this short master work one of the most beautiful chorales ever heard.

J. S. Bach’s inner voice writing. The suspensions and non-chord tones. The expansion into the subdominant.…

There are innumerable reasons why I love this work of art.

When I first sang this chorale with the Monteverdi Chor München during their 2019 Christmas Concert series, I was immediately struck by the soft, almost tender way that this chorale melody is harmonized and presented. What was immediately clear was that this wasn't like an ordinary chorale. It seemed much more inspired, more unique, songlike.

It wasn't until the choir and audience came together in a moment of focus and attention during a concert performance that I was able to truly hear what this piece can do, and I subsequently fell in love with the piece. When I arrived back in NY that winter I transcribed it in a devoted effort to understand it more deeply.

This work is a masterclass on part writing.

Every voice is like a melody able to stand on its own. Like all chorales of Bach, the soprano voice carries the hymn melody, and provides the structure to the whole piece, as I show below.

The other 3 voices are built in such a way where in every moment, it is possible to hear what the others are doing musically. Bach seemed to have spent more time than usual creating a beautiful and crafted line for each voice, placing each dissonance in such a thoughtful way.

To understand non-chord tones, let's first do a harmonic analysis with chord names and their function.

Download a free PDF of this analysis for your studies here. (You can become a free subscriber for more musical content using the form at the bottom of this page.)

Figure 1. Chord names written above the soprano, functional analysis in Roman numerals below the bass. Study to use in your pieces for chord progressions.
**Non-chord tones:**
*app.* is appoggiatura
*sus.* is suspension
*pass.* is passing tone

German text

O Jesulein süß, o Jesulein mild!

Deins Vaters Willn hast du erfüllt;

Bist kommen aus dem Himmelreich,

Uns armen Menschen worden gleich,

O Jesulein süß, o Jesulein mild!

English translation

O little one sweet, O little one mild,

thy Father’s purpose thou hast fulfilled;

thou cam’st from heav’n to mortal ken

equal to be with us poor men,

O little one sweet, O little one mild.

The Form is Given by the Chorale Melody (Soprano)

This score shows the soprano melody with the underlying harmonies represented as the Roman numerals and figured bass.

The melody has 3 big phrases. The first big phrase can be broken into two smaller phrases. The first half of the first phrase ends on the F major chord and features a strong tonicization of F as the dominant of Bb major. This is done by way of the C major chord in measure 2, such that the Bb major chord no longer feels like tonic but subdominant of the dominant, reflected in the IV7/V harmony of measure 3. (C major isn't a diatonic chord of Bb major, so that's why we're immediately pulled away from the tonic.) The second half of the first phrase, starting on measure 6 and ending measure 9, then affirms Bb major with a V-vi-I-IV-V-I cadence in Bb major.

The second big phrase starts on measure 10 and is set mostly around Eb major, the subdominant of the home key. The Ab in the harmony of measure 12 has a strong introverted effect, turning the ear more inward. (The Ab is the seventh belonging to a Bb7 chord in measure 12, which resolves down, half a step, to G, the major third of Eb major in measure 13.)

You can see this lilting pattern to the intervals in the melody bar by bar, starting on the Eb in measure 10 and falling a third, then rising a second, then falling a third, then rising a second again. This continues for another 4 bars. The predictable nature of this melody allows Bach to create gorgeous underlying harmonizations.

The third and final big phrase is a 4 bar concluding phrase. We can hear the diminished A triad (A-C-Eb) function as the seven (vii°) of Bb major in the pickup to bar 18, which strongly and quickly places the ear back home in Bb major. The tonic harmony stays in the first inversion though until the very last measure. Why do you think Bach does so? And, where is the climax of this piece?

When you hear this piece, it's hard to tell that there are only 8 chords that compose it.

Bb. Gm. D. C. F. Eb. Cm. Aº. 8 Chords. That's it.

I. ii. II. IV. V. vi. V/vi. and viiº.

The fact that we remain interested from beginning to end clearly shows the effect that masterful part writing has on the ear.

Each of the 4 voices is so beautifully written.

Look, for example, at how the soprano (the chorale melody) and the bass interact below.

Near the very first sound we hear that tender, falling, downward moving ripple created by the bass, which sets up the characteristic dissonance that gets woven throughout the four part texture.

Now take a look at how the soprano and bass voices relate. The Eb major (subdominant) passage is highlighted in blue in the soprano (measures 10-17). You can see, very clearly, the patterns of repetition that Bach uses that add to the gentle rocking quality of this section. Even visually you can see the bass voice in measure 10 and 12 mirror, and 14 and 15 mirror.

Quick guide to the Figured Bass! The Roman numerals and the chord name are the same thing; they both show the relationship between the diatonic chord and the tonic, in this case, Bb major. For example, ii is the "two" chord, and it is the chord built on the second degree of the Bb major scale. Capital letters indicate a major chord, and lowercase indicate a minor chord. The Arabic numerals next to the Roman numerals show the position of the chord (root position, first inversion, etc). Next to each Roman numeral, 6 means the chord is in first inversion and 3 (or no number) means the chord is in root position. 7 indicates a seventh chord, and in this engraving the positions of the 7th chord is not given. For a review of diatonic chords and how to build progressions with them, check out the article from the 14 day harmony course.

Non-chord tones help make this piece sound so rich. The Non-chord Tones (labeled in red in Figure 1) form special moments of harmonic tension.

When performing a work like this, these dissonances must be treated carefully by listening closely to where they happen and how their impacts and resolutions contribute to the overall phrase.

A guide to 3 types of Non-Chord tones: Vertically, some notes don't fit in with the others in the functional triad chord. While they are crucial to the harmony of the piece, and have a very clear role, they aren't considered in the naming of the chord, which is why they are named as such.

Check out the 5th measure, with the F chord. The notes on the first beat are F-A-C, but there is also a Bb sung by the tenor. The tenor is holding on to the note they were singing the beat before, delaying the resolution to the more consonant A in the F chord, and creates a dissonant interval of a Major Second against the soprano on beat 1. This type of dissonance is known in part writing as an appoggiatura when it occurs on a strong beat. It is a type of suspension.

Consider the bass voice of the same measure: they sing an F, but also dip down a half step to E natural. So, would you analyze this as a F-A-C-E chord, or an Fmaj7 chord? No. This is another example of a non-chord tone, known as a neighboring tone. The bass sings the F, runs over to its E-natural neighbor, and then immediately comes back home to F. If there is a non-chord tone on a weak beat then it isn't labeled, which is the case for this and some of the passing tones.

Now check out beat 3 of bar 12, in the alto voice. The alto melodically passes through the G on its way to F, so it is labeled as a passing tone. The notes on the third beat are Bb-D-F-Ab which spells out a Bb7 chord, but they aren't sung at the same time.

These non-chord tones help make the music much more rich and harmonically and melodically complex.

To gain some insight into how dissonances and consonances can create moments of harmonic tension and release in a musical context, check out my resource on the musical cadence.

The presence of the subdominant creates an overall tender feeling of introversion.

Give this piece a listen to hear what I mean (I strongly recommend a vocal recording, or make your own recording—there are a lot of bad ones out there, sadly) and follow along with the score.

Even better? Play it yourself. This music could be played with any instrumentation, sung in any vocal range, it doesn't have to be just SATB. You can work on it either alone or with other musicians. I'm confident that this one piece alone will improve your musicality and I'm so excited to share with you.