
The shortest books in the New Testament are 2 and 3 John. Both epistles, in the original Greek language, within which they were written, contained less than 300 words, and each could have been written on a single sheet of papyrus, just as they can easily be printed in our Bibles today on a single page.
Whereas 1 John focuses on the prerequisites of church fellowship; namely, the truth about Christ, obedience to Christ, and love for Christ, 2 John focuses on protecting church fellowship, from those who deny the truth of Christ, disobey Christ, and who are disingenuous in their declared love for Christ. While the church—“the elect lady and her children”—are to open her doors and arms to all true followers of Christ, neither the door to the church house nor to the Christian’s home should ever be opened to false teachers teaching false doctrine.
Contrary to popular opinion, Christian hospitality is discriminating. We are neither to greet nor to welcome into our churches and homes anyone who is preaching a false gospel, lest we give credence to their heresy and become a partaker of their evil deed.