A common theme within the NT and early Christian literature is the inevitability and dangerous nature of false teaching. Paul was not the only one to face this issue in ministry or to address it in writing, although some of his writings on this topic are the most well known. In the Olivet Discourse Jesus warned of false Christs and false prophets (Matt 24:24; Mark 13:21). Paul’s apostolic colleague Peter devotes the entirety of the second chapter in his second letter to the character, teaching, and future judgment of the false teachers who will arise in the church. This material in 2 Peter is mirrored in Jude, where the entire central argument of the epistle is against these false teachers. Polycarp warns his readers against false teaching (Pol. Phil. 7:2), and the entirety of Didache 11 is a warning against false teachers with instruction on how to identify them. It is a recognizable theme in early Christian literature that believers recognize and refute false teaching and teachers. Paul deals with that reality head on in the book of Galatians, and the paragraph in Gal 5:7–12 contains his most pointed, confrontational words on this matter.
From this admonition against false teachers come two applications for the believer. First, the believer must seek both to believe and behave in accordance with the truth. The falsity of the teaching against which the early Church wrote is not limited to doctrinal matters; it is often a matter of behavior. In a practical way, this is the situation Paul faced: Likely he and his opponents would agree that Jesus is the Messiah, that he was crucified and rose again on the third day. The difference was their behavior—dependence upon and promotion of circumcision specifically and the Law more generally—was in conflict with that doctrine. The believer who seeks to follow Christ in all things must analyze their behavior as closely as they examine their doctrine. Didache 11:10 speaks to this well: “But any prophet teaching the truth, if he does not do what he teaches, he is a false prophet.” One can teach the truth, but still be false if behavior does not match.
The second application arises from a proper understanding of the function of Paul’s language. In this paragraph Paul speaks as an apostle appointed by God, called directly by him to share the gospel of Christ among the Gentiles. His words come not only from his heart but from his office. As such, Paul’s words carry great weight. But we cannot directly imitate Paul’s stance or take up his apostolic mantle to pass judgment on false teachers. In applying this passage, we do not share Paul’s office. Rather we imitate the role of the Galatians. Our responsibility is to hear Paul’s words in Scripture and measure teaching against them. We cannot know directly as Paul did, without intermediary, that false teaching “is not from the one who calls you” (Gal 5:8). We only know this by careful examination and understanding of the Scripture which God has given us. Our role is to measure teaching against the standard of the biblical text and by so doing discern that which is true and that which is false, embracing the former and rejecting the latter.