What type of composition did Bach write weekly during the latter part of his career?

Bach wrote cantatas on a weekly basis during the latter part of his career, particularly while he was in Leipzig. These compositions were typically intended for church services, aligning with the liturgical calendar. Cantatas often included a mixture of vocal and instrumental elements, featuring soloists, a choir, and an orchestra. They were a key part of the worship experience, with many of Bach's cantatas designed to complement the message of the sermon and devotional practices of the day.

In contrast, symphonies and sonatas are more associated with instrumental music and were not the primary focus of Bach's output during this time. Similarly, while Bach did compose concertos, these were generally fewer in number compared to his cantatas written for the church. Thus, the emphasis on cantatas signifies not only Bach's commitment to his role as a church musician but also his profound ability to blend theological themes with musical expression.