Original: The St Matthew Passion was probably first performed on 11 April 1727 in the St. Thomas Church, and again on 15 April 1729, 30 March 1736, and 23 March 1742.
Simplified: It was probably first performed on Good Friday (11 April) 1727 in the Thomaskirche in Leipzig, where Bach was Kapellmeister. He made some changes to it by 1736 and performed it again on 30 March 1736.