The cantatas of J.S. Bach are among the best known and most frequently performed musical works of the baroque period. However, when they are played and heard today, questions arise that are difficult to answer because the works are being experienced outside their historical context. Such questions concern the role of the cantatas in Bach's compositional development, musical models for the works, and performance practice during the composer's lifetime. In this book, Bach scholars place the works in their historical and biographical context, guiding the reader through their literary, musical, aesthetic and theological features. This volume - the first of three which complement a recording project by the Amsterdam Baroque Orchestra and incorporating the complete Bach cantatas - covers the sacred cantatas he wrote during the first 28 years of his life, before his move to Leipzig in 1723.