In the Babel of conflicting opinions, it is best to notice first the obvious internal phenomena. The first part of the Teaching (now distinguished as chaps. i.-vi.) sets forth the duty of the Christian; in chaps. vii.-x., xiv., we find a directory for worship; chaps. xi.-xiii., xv., give advice respecting church officers, extraordinary and local, and the reception of Christians; the closing chapter (xvi.) enjoins watchfulness in view of the coming of Christ, which is then described.
The most striking internal phenomena are, however, the correspondences of this document with early Christian writings, from a.d. 125 to the fourth century. With the so-called Epistle to Barnabas, chaps. xviii.-xx., the resemblances are so marked as to demand a critical theory which can account for them.