"Meine Seele erhebt den Herren
und mein Geist freuet sich Gottes,
meines Heilandes."
The "Magnificat" (Luke 1, 46-55), a hymn of praise, begins with these sentence above. Its origin are the words spoken by Mary when she visited her cousin Elisabeth and both have been pregnant (Elisabeth was mom of John The Baptist).
The base for the original version of this aria from Bach's cantata "Meine Seel erhebt den Herren"('magnificat anima mea') is the associated Gregorian psalm melody of the Marian hymn of praise (tonus peregrinus), whose tune has remained unchanged throug the times. This tune is assigned to the left hand in the organ version. The special symmetrical form of this introverted piece begins and ends with a pedal solo ritornello, which also provides motifs for the two middle voices; Alto and Tenor are composed as counterpoint motifs, including some chromatic bars.
As "Wachet auf, ruft uns die Stimme" (BWV 645)
https://www.contrebombarde.com/concerthall/music/49416
and "Kommst du nun, Jesu, vom Himmel herunter" (BWV 650),
https://www.contrebombarde.com/concerthall/music/49635
this piece relates to the Advent time.
Recorded with the beautiful OAM-set of Poblet.