Bach was preparing to enter Lorenz Christoph Mizler's Society of Musical Sciences

In 1746 Bach was preparing to enter Lorenz Christoph Mizler's Society of Musical Sciences. In order to be admitted Bach had to submit a composition, for which he chose his Canonic Variations on "Vom Himmel hoch da komm' ich her", and a portrait, which was painted by Elias Gottlob Haussmann and featured Bach's Canon triplex á 6 Voc.