Jan R. Luth The organ as an iconographical and allegorical phenomenon
Het ORGEL 99 (2003), nr. 2, 32-38 [summary]

Whereas the Calvinist point of view is that instrumental music only tickles the ear, the Lutheran tradition never rejected the use of instruments in services. Basing itself on Psalm 150 and other parts of the Bible, the Theological Faculty at Wittenberg said in 1597 that instrumental music was a gift of God, which moves the human mind. It can be concluded that independent instrumental music was common in late 16th-century services.
The organ played a major role in this respect. This was underlined by its design: the panels on the organ in St Anne’s Church at Augsburg (1512, panels from 1520) indicate that organ music is the ‘sun’ among vocal and instrumental music, and that liturgical music and celestial music are connected closely. The latter is also made visible by the music-making angels on the Silbermann organ in the Dom at Freiberg (1714).
In sermons held at organ inaugurations, this was formulated in detail: in 1696, Conrad Feuerlein said, for example, that the stop Grobgedackt referred to God’s covering (‘decken’) of our gross (‘grob’) sins. Organist Johannes Erasmus Kinderman (1616-1655) gave each stop an allegorical significance in a similar way: he said e.g. that the organ stop Principal represented the Holy Trinity.
The placement of the organ was allegorical as well. When it was placed high in the church, as at Waltershausen, Arnstadt and Neuenfelde, it referred to the heavenly music of which it was a part. A well-known example is the placement of the organ and other instruments in the chapel ‘Weg zur Himmelsburg’ at Weimar: over the ceiling; the music descended through an opening of 12 square metres.