The Millerites were the followers of adventist preacher William Miller (1782—1849). The term Millerites was coined by detractors.
Today, when people hear the term Adventist, they might think of a certain denomination or group that has advent in its name (Advent Christian, Seventh-day Adventist, etc.), but at the time of William Miller, adventist simply meant “someone who emphasized the second advent (the return) of Jesus Christ in his preaching and teaching.” Miller was a New England farmer who was largely self-educated. Through his own study of the Bible, putting together clues from various passages, he came to believe in 1831 that the world would end (through the return of Christ) sometime around 1843. Miller published his beliefs in books and pamphlets and also began to hold tent meetings with hundreds in attendance. His followers also began to spread his message.
As 1843 drew near, word of Miller’s prophecies continued to spread, with more and more Americans and the press taking notice. When 1843 passed without incident, a new date, October 22, 1844, was set. One source estimates that as many one million Americans took Miller’s prophecies seriously, but some took them so seriously that they quit work and gave away their possessions. These are the people whom critics and the press dubbed “Millerites.” There are reports that some Millerites even donned white robes and went up to mountaintops to await the Lord’s return, but these reports are disputed and hard to substantiate.
When the predicted end did not take place in 1844, the Millerites disbanded in dismay, and the event became known as the “Great Disappointment.” Miller himself quietly withdrew from the public eye. While he still held that the Lord would return soon, he admitted that the chronology was uncertain. He died a few years later. The Millerites, leaderless now, splintered and formed other groups. The Advent Christian Church and the Seventh-day Adventists developed in the aftermath of Miller’s failed prophecies. There is even some evidence to suggest that Charles Taze Russell, the founder of the Jehovah’s Witnesses, was also influenced by Miller.
It is sad that people look for hidden messages and secret clues in the Bible instead of heeding the plain meaning of Scripture. The words of Jesus are clear: “No one knows the day or the hour” (Matthew 24:36). The words of Jesus notwithstanding, some Bible teachers who should know better continue to set dates for the return of Christ and lead followers astray; many, like the Millerites, make life-changing decisions based on the “prophetic” teaching. The gullible are inevitably disappointed as the “prophetic” date passes. The biblical attitude is to be ready for Christ to return at any moment, but to make plans for the future as if He will not return in our lifetime. Disengaging from the world to wait for Christ to return is a misapplication of the doctrine of Christ’s second coming.