Bach leads the first performance of his cantata Erfreut euch, ihr Herzen, BWV 66, his first cantata composed for Easter in Leipzig.

Johann Sebastian Bach was a German composer and musician of the late Baroque period. He is known for his prolific output across a variety of instruments and forms, including the orchestral Brandenburg Concertos; solo instrumental works such as the cello suites and sonatas and partitas for solo violin; keyboard works such as the Goldberg Variations and The Well-Tempered Clavier; organ works such as the Schübler Chorales and the Toccata and Fugue in D minor; and choral works such as the St Matthew Passion and the Mass in B minor. Since the 19th-century Bach Revival, he has been widely regarded as one of the greatest composers in the history of Western music.

Erfreut euch, ihr Herzen, BWV 66.2, BWV 66, is a church cantata for Easter by Johann Sebastian Bach. He composed it for the Second Day of Easter in Leipzig and first performed it on 10 April 1724. He based it on his congratulatory cantata Der Himmel dacht auf Anhalts Ruhm und Glück, BWV 66.1, first performed in Köthen on 10 December 1718.

April 10 is the 100th day of the year in the Gregorian calendar; 265 days remain until the end of the year.