Jesus nahm zu sich die Zwölfe, BWV 22 Weimar did not dismiss him and arrested him for disobedience. He was released on 2 December 1717. In Köthen, Bach found an employer who was an enthusiastic musician himself. The court was Calvinist, therefore Bach's work from this period was mostly secular, including the orchestral suites, the cello suites, the sonatas and partitas for solo violin, and the "Brandenburg Concertos". He composed secular cantatas for the court for occasions such as New Year's Day and the prince's birthday, including . He later parodied some of them as church cantatas without major changes, for example . Bach composed his cantata as
Piano concertos by Wolfgang Amadeus Mozart of "fiddling" with all the themes, instead is left with the ritornellic impression: Mozart truly uses "art to conceal art". One further point of great importance is the interaction between piano and orchestra. In the earlier concertos, such as the not totally successful No. 13 in C major, and even more so, perforce, in the concertos for two and three pianos, the interaction between the two is limited, but the later concertos develop the subtle relations between them to a high degree; for example, in No. 16, K. 451. His later concertos are truly described as concertos for "piano and