“I do not fear Islamic Jihadists nearly as much as I fear the Christian church in the West departing from biblical orthodoxy.” That was how I opened a speech I made recently to the National Religious Broadcasters convention in Nashville, Tennessee. What gives that fear such certainty is the knowledge of a historical fact—namely, throughout history, Islam grew when Christianity was weakened through its departure from biblical authority. There is no doubt that Islam grew out of a corpse of a church that was beset with heresy and apostasy. Immediately prior to the rise of Islam, viruses of false gospels...