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Not to be confused with the Gospel of Barnabas, the Epistle of Barnabas, also known as the Letter of Barnabas, is an early writing of Christianity, frequently mentioned by other church fathers. Although it is named for Barnabas, an associate of Paul, the letter itself does not mention its author. Rather, this connection was made by commentators such as Clement of Alexandria. This dates it somewhere in the late first to very early second century. The text gives insight into Old Testament Jewish laws and traditions, comparing and contrasting them with Christian practice under the New Covenant.
The term gnosis, meaning “knowledge,” is used by the Epistle of Barnabas to describe its message. However, the content contradicts early heresies such as Gnosticism, and it seems to reflect an orthodox, early understanding of the faith. At the same time, some writers criticized it for relying heavily on oral traditions about the Old Testament—the Mishnah—as well as use of gematria or biblical numerology.
Early church fathers referenced the Epistle of Barnabas, including Origen, who seemed to think it was an authentic writing of Barnabas. The text was included at the end of some early copies of the Bible, where it might have been considered as a reference. Most early Christians did not seem to consider it part of inspired Scripture; however, it was valued for its insights into Jewish theology. That perspective is best described as interpreting the Old Testament through the lens of early Christianity. Those explanations make up most of the letter.
The last section of the Epistle of Barnabas describes a series of positive commands, followed by their opposites. These are contrasted as the Way of Light and the Way of Darkness, respectively. The Way of Light reflects a heavily Jewish understanding of Christian behavior and morals. This is followed by the Way of Darkness, also called the Way of the Black One, referring to Satan.
While not a part of the canon of Scripture, the Epistle of Barnabas is still a valuable resource. Early church fathers recognized its usefulness, even as they agreed it was not divinely inspired. Whether or not the Epistle of Barnabas was actually written by Barnabas himself, modern believers can read it from the same cautious perspective.