Advent Christian Church

William Miller, a Baptist lay preacher and former army officer from upstate New York, began teaching in the 1830s that biblical prophecy pointed to the imminent bodily return of Christ, initially calculating that the event would occur sometime before March 21, 1844. When that date passed without incident, Miller and his followers, who had become known as Millerites, revised the calculation to a new date, October 22, 1844, and when Christ again failed to appear, the failure became known among Miller's followers as the Great Disappointment, a crisis that scattered and demoralized a movement that had drawn tens of thousands of adherents across the northeastern United States. A Mutual Conference of Adventist believers met in 1845 to work out what had gone wrong and what should be preserved from Miller's teaching, and the movement split into several distinct bodies over the following fifteen years as different groups reached different conclusions: the Advent Christian Church itself formally organized as the Advent Christian Association at a conference held in Salem, Massachusetts, in 1860, while a separate line, more directly disagreeing over the seventh day Sabbath question, organized as the Seventh-day Adventist Church in 1863.

The Advent Christian Church shares with the larger Seventh-day Adventist Church a common Millerite ancestry and a shared emphasis on the literal, imminent, and personal return of Christ, but the two bodies parted ways on several specific doctrinal points that have kept them organizationally separate ever since. Where Seventh-day Adventists adopted Saturday, the seventh day, as their day of worship, the Advent Christian Church retained the conventional Sunday worship practiced by most other American Protestant denominations, treating the Sabbath question as one on which Miller's original movement had not settled and did not need to settle uniformly. More distinctively, Advent Christians historically teach conditional immortality, the belief that the soul does not automatically survive death in a conscious state but instead sleeps in an unconscious rest until the resurrection, and that only the redeemed are then granted eternal life, while the unredeemed simply cease to exist rather than facing conscious eternal punishment, a position known as annihilationism that sets the denomination apart from the majority of historic Christian teaching on the afterlife. This distinctive combination, an undated but urgently expected second coming, Sunday worship, and conditional immortality, has defined the small denomination's identity since its nineteenth century organization.