There is a curious connection between the Didache  and the Epistle of Barnabas relating to the issue of dualism. Although neither the Didache and the Epistle of Barnabas are particularly well known as works, there are notable ways in which both of these epistles show very similar concerns relating to the supposed Ways of Dark and Light. Given these similarities, it is thought that either one borrowed from the other or that both borrowed from a common source, and many contemporary scholars  argue for the third option. While it is not my intention to go into detail about the relationship between the two, as that would overwhelm the broad approach of this particular project, those who are interested can look up the material on a much deeper level. What I would like to do here is introduce the reader to this material such as it exists and to point out the importance of dualism in a general study of early Christian writings.
The two ways are introduced in section 18 of the Epistle of Barnabas in the following way: “Now let us pass on to quite a different sort of instruction and knowledge. There are two Ways of teaching, and two wielders of power; one of light and the other of darkness. Between these two ways there is a vast difference, because over the one are posted the light-bearing angels of God, and over the other the angels of Satan; and one of these two is the Lord from all eternity to all eternity, while the other stands paramount over this present age of iniquity (179).” Likewise, when we look at the Didache, we see the following introduction of the two ways in section one: “There are two Ways: a Way of Life and a Way of Death, and the difference between these two ways is great. The way of Life is this: Thou shalt love first the Lord thy Creator, and secondly thy neighbor as thyself; and thou salt do nothing to any man that thou wouldst not wish to be done to thyself (191),” and the following introduction to the way of death at the beginning of section five of the Didache: “The Way of Death is this. To begin with, it is evil, and in every way fraught with damnation (193).”
Obviously, this dualism suggests a similar worldview between these two texts. Nor is this dualism a particularly unfamiliar mindset in our own world. In our contemporary political and religious struggles many of us (myself included) have a marked tendency to see ourselves and those who agree with us as being children of life and the light and those who are hostile and opposed to us as children of dark and of death. It should therefore come as little surprise that we see this same tendency in the ancient world, as dividing the world into two poles is a fairly common one and something that attracts little commentary except among those whose attempts to erase those polarities in our existence mark them off as children of darkness and evil because they resent the sharp division between the two. Those who wish to be children of the gray are children of the darkness who want to appear as children of the light, and such a situation is also lamentably common and has been so from time immemorial as well, so that it ought not surprise us at all.
Nor is this dualism absent from the Bible. Paul remarks in Ephesians 5:8-9: “For you were once darkness, but now you are light in the Lord. Walk as children of light (for the fruit of the Spirit is in all goodness, righteousness, and truth).” Likewise, in Philippians 2:14-16 we read: “Do all things without complaining and disputing, that you may become blameless and harmless, children of God without fault in the midst of a crooked and perverse generation, among whom you shine as lights in the world, holding fast the word of life, so that I may rejoice in the day of Christ that I have not run in vain or labored in vain.” Nor is this dualism absent among the rest of the scriptures, for as John writes in 1 John 2:7-11: “Brethren, I write no new commandment to you, but an old commandment which you have had from the beginning. The old commandment is the word which you heard from the beginning. Again, a new commandment I write to you, which thing is true in Him and in you, because the darkness is passing away, and the true light is already shining. He who says he is in the light, and hates his brother, is in darkness until now. He who loves his brother abides in the light, and there is no cause for stumbling in him. But he who hates his brother is in darkness and walks in darkness, and does not know where he is going, because the darkness has blinded his eyes.”
We may see, therefore, that there is some aspect of dualism that is present in the Bible and a similar form of dualism that we see in some of the early writings of professed Christians among the Apostolic Fathers. Given the immense sense of opposition that many early Christians (whether or not they were genuine followers of Christ) felt in comparison to persecuting Roman authorities and rival in the Jews or among others who professed Christianity with different belief systems, dualism, with its sharp divide of the world into good and evil, was certainly an appealing option. The fact that such an approach remains an appealing option for those of us engaged in struggles and rivalries and arguments and debates with other parties in our contemporary world suggests that dualism offers a pleasant way of overcoming the normal barriers to successful polemics that are sometimes faced in people who may not be considered as being that different from others. Certainly its ubiquity in the ancient world and in the contemporary one suggests it must serve some useful purpose or else we would find some other way of dealing with hostility and disagreements with others.
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