Answer
The Great Disappointment describes an episode in Seventh-day Adventist history when followers of William Miller (1782—1849) became bitterly disillusioned after his 1843 and subsequent 1844 predictions for the second coming of Christ failed to come to pass.
William Miller was a farmer and army captain who served in the War of 1812. In 1816, Miller converted from Deism to Christianity and began to study the Scriptures. Eventually, in 1833, he became a licensed Baptist minister.
After fourteen years of Bible study focused mainly on the books of Daniel and Revelation, Miller believed that he had uncovered the key to Daniel’s prophecies. In 1831, Miller predicted that the second coming of Jesus Christ would take place within a year of March 21, 1843. Miller’s ideas were published in 1836 in a book titled Evidence from Scripture and History of the Second Coming of Christ, about the Year 1843.
Over time, Miller’s preaching about the return (or second advent) of Christ attracted widespread interest among Baptists, Methodists, and Presbyterians in America. These followers, labeled Millerites by critics, numbered in the hundreds of thousands as the predicted date drew near. Some of these Americans quit their jobs and gave away their possessions, utterly convinced that Christ’s return was imminent and sure.
When the anticipated time came and went without event, Miller recalculated a more specific date for Christ’s return and settled on October 22, 1844. When that date also passed without the Lord’s return, most of Miller’s followers abandoned the movement, and Miller himself retired into relative obscurity and died a few years later. Those who had embraced Miller’s adventist preaching experienced great grief and sorrow—they had truly believed that they would be transported to heaven in 1844, but it didn’t happen. Their lives went on as before. The event became known as “the Great Disappointment.” Those who stayed in the movement called themselves the “remnant” and formed the foundations of the Seventh-day Adventist Church and Advent Christian Church.
Later Adventists attempted to save face concerning the Great Disappointment by reinterpreting the prophecies upon which Miller had determined his dates. Rather than being the time of Jesus’ return to earth, they said, October 1844 was the start of Jesus’ final atoning work. According to the remnant, it was when Jesus entered the Most Holy Place in the heavenly sanctuary to begin judging who would be saved—His final action before His second coming.
Miller was not the first or last misguided preacher to forecast the end of the age, but he may have been the most persuasive and notorious in recent Christian history. The Great Disappointment could have been avoided if only Miller and his followers had grasped a crucial biblical truth. Yes, followers of Jesus Christ are called to live in confident expectation of the Lord’s return at any moment (Titus 2:13). And Revelation 22, the last chapter in the Bible, reassures us that Jesus Christ is coming soon. Miller was right on that essential. But for all his study of Scripture, Miller missed a vital truth. Our expectation of Christ’s second coming is to be tempered with this fact that Jesus made very clear: “But about that day or hour no one knows, not even the angels in heaven, nor the Son, but only the Father” (Matthew 24:36). God has specifically chosen not to reveal the day or time of Christ’s return.