Muilenburg, James. "Chapter Three: Early Literary History." The Literary Relations of the Epistle of Barnabas and the Teaching of the Twelve Apostles. Marburg, 1929, 22-47.
External evidence for the dating of both the Epistle of Barnabas and the Didache is necessary. The Epistle has only two possible internal references which could indicate a date, and they are not clear. The Didache has no internal indicators of a date (Muilenburg 1929, 22). However, Muilenburg is cautious, noting that some parallel wording or ideas do not necessarily signify dependence but may simply point to a similar commitment to like ideas. He goes on to list numerous similarities between the Epistle and other deatable works, but finds the similarities not to make one certain of literary dependence (Muilenburg 1929, 23). Then again, a relationship which does not demonstrate dependence may still be of value. It is a challenging matter to assert the value of a given parallel (Muilenburg 1929, 24). Muilenburg provides numerous examples of similarities. He finds that Clement of Alexandria, probably about 215-216, mentions the Epistle clearly (Muilenburg 1929, 25). Tertullian makes a possible reference, but may be conflating it with Justin Martyr. Psueudo-Cyprian and Hippolytus make possible allusions, but they are not clear references. Origen does seem familiar with the Two Ways (Muilenburg 1929, 26). The fragmentary Latin Didache has several passages in which there seems to be a familiarity with the Epistle, particularly 18. and 18.2 (Muilenburg 1929, 27). We observe, however, that the bulk of these indications of familiarity are relatively late and provide no help in identifying a date of composition.
Muilenburg further evaluates the integrity of Barnabas. Some of the passages which are not present in all the versions are also absent in parallels with Clement of Alexandria (Muilenburg 1929, 28). The letter is only known in Alexanddria prior to the fourth century and is ascribed by Clement and Origen to Barnabas, the companion of Paul (Muilenburg 1929, 30).
Muilenburg asserts that "The literary relations between the Teaching of the Twelve Apostles and the Epistle of Barnabas, on the one hand, and between the Teaching and the Shepherd of Hermas, on the other, constitute one of the most complex problems which extra-canonical Christian literature has bequeathed to us (Muilenburg 1929, 32). There is specific debate about priority between Hermas and the Didache. Muilenburg specifically reviews some of the arguments of Schaff, which he does not always consider sound (Muilenburg 1929, 32ff). Likewise, Muilenburg considers the attempts to demonstrate that Clement ws familiar with the Didache to be "questionable" (Muilenburg 1929, 36). Muilenburg details the alleged parallels between the Didache and works of Clement. He then continues with citations of Eusebius and Athanasius as they identified writings to be accepted or rejected (Muilenburg 1929, 38-39). This does not particularly add to discussion of literary relationships, but it does make it clear the writings were known. One of the challenges, which is not often stated (includin by Muilenburg), but which appears in repetitive use of language, is that the works speak of a way of good and a way of evil. These themes are routinely present in literature, especially of a religious nature, thus confusing the field of inquiry.
Two Ways documents were known in early Christianity. The Didache contained one, but, as Muilenburg observes, was not limited to that. This was apparently recognized by Athanasius, who cited the Two Ways and other parts of the Didache (Muilenburg 1929, 42). Yet, for some reason, scholarly attention has focused on the Two Ways material.