Differences from other musical forms
The Italian solo cantata tended, when on a large scale, to become indistinguishable from a scene in an opera, in the same way the church cantata, solo or choral, is indistinguishable from a small oratorio or portion of an oratorio. This is equally evident whether we examine the unparalleled church cantatas of Bach, of which nearly 200 are extant (see List of Bach cantatas), or the Chandos Anthems of Handel. In Johann Sebastian Bach's case many of the larger cantatas are actually called oratorios; and the Christmas Oratorio is a collection of six church cantatas actually intended for performance on six different days, though together forming as complete an artistic whole as any classical oratorio.