The rapture is the belief that either before or after Christ returns the Christians still alive on earth will be transformed, receive their resurrected bodies, and be taken in the clouds with Jesus. This is based entirely on Paul’s words in 1 Thessalonians 4:16-18.
Again, there is debate amongst eschatologists about the timing of the rapture. They are divided into three camps: Pretribulation, Midtribulation, and Posttribulation.
Pretribulationists believe the rapture will occur at the beginning of the 7 year tribulation period. This means no believers will experience any tribulation period. This belief holds all believers on earth will be members of the restored Jewish nation.
Midtribulationists believe the rapture will occur at the halfway point, 3 1/2 years before the return of Christ at the very beginning of the Great Tribulation period.
Posttribulationists believe the rapture will happen when Christ returns at the very end of the Great Tribulation or 7 year time frame before Christ returns. The church will continue throughout the tribulation.
Paul also discusses the rapture in 1 Corinthians 15:20-23, 51-52.
Some scholars even profess a partial rapture where only the pious Christians will be taken with Christ while the rest must suffer first and then be taken.
The rapture and Christ’s Second Coming are different events although both involve the End Times. The rapture is where Christ gathers the believers in clouds. The Second Coming is where Christ returns to earth to establish his kingdom, defeat the AntiChrist, and judge non-believers and end the tribulation.
Keep in mind all of these are theories. We know the rapture will occur. We don’t know when. God does not tell us. We know Christ will return. God does not tell us when. Furthermore, Scripture doesn’t expressly teach one view over the other. Thus, what we have is man trying to determine God’s ways given what little we are told in the Word. There is nothing wrong with this; in fact it is our job as Christians to try to divine what God is telling us.
We just have to remember our knowledge is limited and in the end only one thing matters: we will be with God. In the meantime, we live like He tells us to live. God will take care of the rest.