The four letters in this volume all deal with heretical teachings within the early Church. Dr. Barclay describes the various forms in which Gnosticism appeared in I John, pointing out that some of its positions, such as the notion that the material world, including the human body, is evil, still infect the thinking of some Christians. II and III John are warnings against wandering preachers who, on occasion, taught false doctrines and against individuals within the Church who repudiated the writer's authority. Jude is a strong indictment of men of bad morals (antinomians) who had insinuated themselves into the Church.