"Bist du bei mir" (If you are with me) BWV 508 is an
aria in the Notebook for Anna Magdalena Bach. It was
therefore attributed to Johann Sebastian Bach, but the
melody is part of the Gottfried Heinrich Stölzel opera
Diomedes, oder die triumphierende Unschuld that was
performed in Bayreuth on November 16, 1718.
Although the opera score is lost, the aria had been
part of the Berlin Singakademie music library and it
too was considered lost in the Second World War, until
it was rediscovered in 2000 in the Kiev Conservatory.
The continuo part of BWV 508 is more agitated and
continuous in its voice leading than the Stölzel aria;
it is uncertain who provided it, as the entry in the
Notebook is by Anna Magdalena Bach herself.
In an essay in the Bach-Jahrbuch 2002, Andreas Glöckner
speculates that either she obtained the song from the
inventory of the Leipzig Opera that had gone bankrupt
in 1720, or that it simply was a favorite known to
nearly everybody in Leipzig that was particularly
suitable for Hausmusik.
Although originally created as an organ opera aria, I
adapted this work for flute and piano.
The piece has become a very popular choice for wedding
ceremonies and other such occasions.