This fourth book of the Bach cantatas series is concerned with the twenty-three cantatas for Advent, Christmas, New Year, and Epiphany, as well as the six cantatas of the Christmas Oratorio. The analytical approach to Bach's cantatas, I have found, necessarily changes after the Trinity Sundays and feasts, as the Trinity cantatas are concerned with matters of faith and generally are didactic, whereas the subsequent cantatas in the Lutheran liturgical year deal with the life of Christ and tend more to narrative. It is narrative, however, imbued importantly with concerns relating to salvation, the forgiveness of sin, the loss and regain of paradise, and the relationship between life, death, and afterlife.

The structural approach I adopted in the previous three books remains unchanged. I treat the cantatas as they relate to the sequence of the liturgical year of worship. There are other approaches possible, such as ones based on chronology of composition or theological themes, but my primary interest was to assess and investigate how the church year would function for congregations, both Bach's and ours, as well as the extended congregation, so to speak, to whom the cantatas continue to appeal to today. My primary focal point is neither musical analysis nor musical history. My objective is relevance, and how I understand it, and how I am to communicate with readers who share intellectual and emotional aspects that emanate from and inform such an approach.