This short piece is a two-voice piece for organ and was published after he had moved to Leipzig, in 1739, as part of a treatise of organ pieces. Scholars believe it was likely inserted as Bach’s take on theoretical squabbles on the subject of 2 part counterpoint. Bach was in a position with these pieces to show off his industry with choosing complex themes and constructing those that would go beyond the complexity he had introduced earlier in his 2-part inventions and 3-part sinfonias for keyboard.