October 22, 1884.
Jesus came back on this date in 1884. Did you miss it? Yeah, so did everyone else.
Baptist minister William Miller, ignoring Christ's statement in Matthew that na man knows the day or the hour except God Himself, decided to predict Christ's return. He looked through history, took the traditional 'day=year' interpretation of Daniel 8 to heart, and decided that October 22, 1884 was The Day(tm).
He got together about 100,000 of his closest followers, and they sat on hillsides all over the world to wait.
When it became obvious to everyone that Jesus wasn't coming back that day, one of the leaders got up and made this statement: "I never did fix upon the precise time myself, and I always told my brethren they would get into trouble if they did; but they would not listen to me, but followed other leaders...I believe the most important thing after all is, to be ready..." Of course, he was one of them sitting on the hill waiting, so you have to wonder about his sincerity at that point.
It is dangerous to start setting dates. I can remember the sensation caused by the book 88 reasons Why the Lord Will Come Back in 1988
. I'd LOVE to have been able to interview the author in 1989 or 1990 and ask him what happened. I think you can still find this book in used bookstores, though if I'd written the thing I'd be travelling the country buying up all the copies I could find, and burning them.
Date setting is fun, and popular. Nothing draws a crowd better than "Come to the revival meeting tonight, and I'll tell you when Jesus is coming back!"
Unless the answer is "Pretty Soon!", don't believe it. Christians are commanded to be busy until He comes back -- so that when He gets here, He finds we've been doing what we're supposed to. THAT is the lesson we can learn from the Millerites.