Music Notes: Bach, Numbers, and the Decalogue

bryan anderson music notes

As we typically do on the first Sunday of the month, this week we will hear the Decalogue, or Ten Commandments, at the beginning of our service.  This time I decided to pair a work with it as an opening voluntary that is based on the traditional Lutheran sung version of the Decalogue, the chorale “Dies sind die heil’gen zehn Gebot,” in a setting by J.S. Bach.  It is a fascinating puzzle box of a work and I thought I’d share its background here.

This work is one small part of a collection Bach titled “Clavierübung III,” also referred to as the German organ mass; it is a work which dips into numerology on almost every page.  That is nowhere more true than in the setting of the Ten Commandments chorale, which conveniently even has a number in its name!  The musical texture is of two voices in canon (like a round) presenting the tune with solidity and squareness, accompanied by two pleasant and tranquil figural voices in the upper parts.  The presentation of the Decalogue theme in two voices calls to mind the two stone tablets upon which the law was given to Moses.  The accompaniment reminds us that the Law is not always a scary concept in its Old Testament exposition.

The number 6 was considered a “perfect” number by St. Augustine in De civitatis Dei, exemplified by the pronouncement of Genesis 1:31 at the end of the six-day creative process: “and behold, it was very good.”  As a number whose factors sum to itself (1+2+3), this symbolism of 6 was carried through medieval and Reformation art and thought.  Not only is “Dies sind” written in six-beat meter, but it contains 60 bars as a whole. As we have seen 6 (perfection) and 10 (law) elsewhere in the work, 60 must be interpreted as 6×10, and we are left with a picture not of the fear of the law, but of Psalm 19:7: “The law of the Lord is perfect, refreshing the soul.”