An interesting and illuminating light is thrown upon Bach’s attitude toward the composition of his church music, especially the cantatas, when we remember that they were all written, not for universal fame or popular acclaim, but for the use of his own choir and for the edification of that particular congregation for whom it was his business to write music. He wrote them, exactly as the minister wrote his sermons, as personal contributions to the effectiveness and completeness of individual church services and occasions. There is little evidence to show that the congregation looked upon these masterly compositions in any other light than as regular and necessary parts of the ordinary routine of service, little dreaming that a future century would give them such lofty valuation. The church cantatas[61] reveal an astonishing versatility and range of expression which show how completely he surrendered his merely technical musicianship to the guidance of the sentiment and mood of the texts, and the needs of their liturgic environment. In these cantatas he has bequeathed to his church and nation ‘a treasury of religious song compared with which, for magnitude, diversity, and power, the creative work of any other church composer that may be named--Palestrina, Gabrieli, or whoever he may be--sinks into insignificance.’[62] In length they vary from four to seven movements, frequently with an instrumental prelude or overture. The shortest consume about twenty minutes in performance and the longest an hour or so. They are all written with accompaniment for organ and, usually, some solo instrument or group of instruments. The vocal numbers consist of recitatives, arias, duets, and choruses. In no other eighteenth-century composer does the recitative assume such qualities of expressive and fluent melody as in Bach. The arias vary greatly in form, ranging from the use of the _da capo_, which in his hands loses its Italian superficiality and conventionality, to the utmost freedom of melodic design. In the choruses he found full opportunity for indulging his characteristic fondness for elaborate and complex polyphonic structures. His conception of the relation of the voice-parts to the whole tonal scheme differed radically from contemporary usage. To him the solo part was not a thing complete in and of itself, but rather a contrapuntal detail of a larger tonal unit. Hence the accompaniment usually rises to melodic importance coordinate with the voice-part. Sometimes, indeed, the voice-part sinks to secondary consideration, and merely concertizes with a more significant theme assigned to the organ or some solo instrument. Bach’s whole mode of thought was so essentially instrumental in its coloring and expressional devices that he frequently produces results that are hardly consonant with what might be called vocal idiom. Such a mode of treatment easily lapses into monotony and over-austerity, of which there are occasional instances in