From the separateness of the Church two results, according to Peter, should follow—in the first place purity, and in the second place courage. Members of a holy race, purchased by the precious blood of Christ, elect from before the foundation of the world, cannot engage in those evil practices which were natural to them in their former state. And citizens of a heavenly commonwealth, members of a holy family, with Christ as their supreme example of courage and self-denial, can never fear anything that men can do.
J. Gresham Machen, The New Testament: An Introduction to its Literature and History, p. 255.