This book is intended to provide the inquisitive listener with a guide to exploring the many layers of meaning found in Bach's Christmas Oratorio. The first section offers a general sketch of the specific context in which this composition was created at the end of 1734, shedding light on the work's liturgical function and taking a closer look at the biblical and broader religious themes. This first section will also focus on the contemporary textual and musical components of the oratorio genre, of which Bach's composition is a prime example. The second section is a detailed discussion of the 64 movements making up the work, with a focus on three aspects: the text, the music and the relation between the two. The nature of the musical setting and its structure depends on the nature of the text, be it prose (the Bible story) or poetry (the chorales and the inserted commentary), narrative or dramatic (indirect or direct speech). Moreover, the music was governed by the particular musical canons of the day, which largely determined and regulated the structure of each section and the coherence between successive sections or those at a greater remove from one another. In order to get to the essence of Bach's oeuvre, the reader-listener must be prepared to become immersed in the literary and musical idiom, the specific terminology and 'grammar' of the day.