According to the unanimous testimony of the ancient Fathers, the author of the epistle was the Apostle Barnabas, a companion of the Apostle Paul. However, modern patrologists largely reject his authorship based on an analysis of the text. The work was written after 70 CE. In ancient times, many Fathers included the text of the epistle in the canon of the New Testament. In the Codex Sinaiticus, it is placed after the Apocalypse.
The epistle resolves the contentious issue of Christianity's relationship to Jewish law: the author seeks to demonstrate that Judaism has been abolished by the Lord's saving work, as foreshadowed by the Old Testament prophets. The epistle contains 21 chapters; with the exception of the introduction and conclusion, it is divided into two unequal parts, the first (2–17) dogmatic, the second (18–20) moral.
The first part reveals the essence and meaning of the Old Testament. The Jews misunderstood the law, which must be interpreted not by the letter, but by the spirit. The evidence of the Old Testament declares the sacrificial cult instituted by Moses and the Jewish ritual services to be of no significance and invalid. The author then explains the purpose of the incarnation of the Son of God and the atoning death of Christ.
The author then examines Old Testament ordinances in detail. Thus, Old Testament circumcision should be understood spiritually—as the circumcision of a person's hearing and heart. Dietary laws have a moral and mystical significance: the prohibition against eating the meat of certain animals implied abstinence from the sins embodied by these animals. The Jews misunderstood what was said about the Sabbath and the temple: the Lord spoke of the Sabbath that would be celebrated at the end of time; as for the temple, the Lord spoke of the temple of our hearts, in which God dwells.
The second part of the epistle contains a teaching on morality, exemplified by two opposing paths of life—the path of light and the path of darkness (eternal death). On one are the angels of God, on the other, the angels of Satan. The path of light consists of loving the Creator and Redeemer and keeping His commandments, confessing one's sins, praying with a pure heart, and so on. The path of darkness is all that destroys the souls of men.
The author concludes the epistle with a request to follow his instructions and a reference to the imminent coming of the Lord. He demonstrates that the Law of Moses has eternal significance in its spiritual meaning, making it binding on Christians as well.
* The title of the essay in Greek – Βαρναβα ἐπιστολή.