This question has been discussed and debated throughout church history and one’s interpretation of this passage depends significantly on whether one believes that these events took place in the first century (the Preterist view), or whether they describe events yet to come (the Futurist view).
The classic rapture theory is based on 1 Thessalonians 4:17 and says that Christians will be “caught up in the air” with Christ and then head off to heaven for a period of time.