The Bible is clear that Jesus will return one day for those who trust in Him alone for their salvation.
“In My Father’s house are many mansions; if it were not so, I would have told you. I go to prepare a place for you. And if I go and prepare a place for you, I will come again and receive you to Myself; that where I am, there you may be also” (John 14:2-3, NKJV).
But He also said clearly that when this will occur is a mystery.
“But of that day and hour no one knows, not even the angels of heaven, but My Father only. […] Watch therefore, for you do not know what hour your Lord is coming. […] Therefore you also be ready, for the Son of Man is coming at an hour you do not expect” (Matthew 24:36,42,44, NKJV).
Contrary to what Jesus said, Harold Camping of Family Radio (not to be confused with American Family Radio) has said he knows that the rapture would occur and God’s final judgment begin on May 21, 2011.
But he also predicted the day would be September 6, 1994. It wasn’t.
The Bible says that Prophets of God will be 100% accurate in what they foretell. If they are wrong in any point, they are false prophets (Deuteronomy 18:21-22), and God tells us “[Y]ou shall not be afraid of him” (v. 22, NKJV).
Instead of predicting days, and worrying about others’ false predictions, Jesus instructs us in Matthew 24 to serve Him faithfully every day and be prepared for His coming…whenever it may be.
[NOTE: Camping’s predictions were supposed to come about (according to supporters) around 6pm on May 21. I wrote the preceding paragraphs around 4pm Central time on the same day, and posted them on Facebook at http://is.gd/oA20JZ.]