Nun komm, der Heiden Heiland

Andreas Kneller (23 April 1649 – 24 August 1724) was a German composer and organist of the North German school.

Born in Lübeck, he was the younger brother of portrait painter Sir Godfrey Kneller. Nothing certain is known about his musical education, though he may have learnt from Franz Tunder (1614–1667), organist of St. Mary's Church, Lübeck, or his own uncle Matthias Weckmann (ca. 1616–1674), organist of St. Jacob's Church, Hamburg. In 1667, he became organist of the Marktkirche in Hanover, succeeding Melchior Schildt (1592–1667). In 1685, he moved to Hamburg, where he became organist of the Petrikirche. It was there that he made the acquaintance of Johann Adam Reincken; he went on to marry his daughter Margaretha Maria in 1686. Kneller's son-in-law Johann Jacob Hencke became his assistant in 1717, and succeeded in him in 1723. Kneller was well respected as a musician, and often acted as an examiner of organs and organists. He was part of the group that examined the candidates for organist at the Jacobikirche, Hamburg, in 1720, which included J.S. Bach (though he did not appear for an audition, he was still chosen for the post but had to decline).

His surviving compositions consist of a few works for organ, typical of the North German baroque toccata form: free passages alternating with fugal sections; this style was described as 'a free way of composition, not subject to any constraints' by Athanasius Kircher (1601-1680), and is thus a sort of stylus phantasticus.

"Nun komm, der Heiden Heiland" is the ancient and prominent hymn usually sung on Advent Sunday. The melody was composed by Martin Luther, and based upon the ancient plainchant melody. The hymn was printed in the Erfurt Enchiridion in 1524, and was also published the same year in Walter's choral Wittenberg hymnal.

Kneller's version is from a partita of eight parts, but apparently only these two variations survive.

The score is attached below, as well the version of the hymn published in 1524.