Ton Koopman and his friend, the bass Klaus Mertens , present a selection of Bach's Sacred Songs. Such songs are drawn in part from Anna Magdalena Notebook, and mainly from the so-called Schemelli Booklet. Schemelli was the editor of a collection of Songs named Musical Hymnbook, whose melodies are by Johann Sebastian Bach. Ton Koopman accompanies Klaus Mertens on the Teschemacher organ in Oosterland (1762).

Only from the mid-1730s does Bach seem to be concerned with composing songs to contemporary lyrics. We find such a small series especially in the second piano booklet for Anna Magdalena Bach. He and his wife composed some "new songs" that certainly enriched everyday life in the family, such as making music together in the evening or prayers at home with their children. Among these six songs, there are especially those whose lyrics provide comfort.

The songs of the musical hymnbook have been given their title "Schemelli-Lieder" after the editor Georg Christian Schemelli (around 1680–1762). Schemelli is certainly responsible for the main selection of 954 songs and thus also for the selection of Bach settings to music.

The publication was titled Musicalisches Gesang-Buch (Musical Hymnbook) and contains 954 "witty, both old and new songs and arias, with well-set melodies, in discant and bass". In the preface of April 24 , 1736, the Naumburg superintendent Friedrich Schulze wrote the following:

The melodies contained in this Musicalisches Gesang-Buch are by Johann Sebastian Bach, Master of the Chapel Choir and Choir Conductor. Musicians in Leipzig, partly composed completely new, partly also improved by him in the basso continuo.

Of 69 songs with (mostly) figured bass, 21 are hymnologically detectable for the first time in this printing. Exactly these 21 songs were therefore taken as the basis for the selection here from the Musicalisches Gesang-Buch in addition to the mentioned small selection from the second book of sheet music of Anna Magdalena Bach.

The order of the 21 selected songs for the present production was based on musical aspects, e.g., related key combinations between songs. The performers also made a subjective selection from the multitude of printed verses.