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 elevated to the most prominent position among the instruments. These works, with their alternation of orchestral "tuttis" and passages for solo display, in turn owe their structure to the tradition of Baroque operatic arias, from which the first movements of Mozart's piano concertos inherited their basic ritornello form. A similar structure can also be seen in the violin concerti of, for example, Vivaldi, who established the form, along with the three-movement concerto structure, and Viotti, wherein the concerto is divided into six sections. The keyboard parts of the concertos were almost invariably based on material presented in the ritornelli, and