The Bible does not specify an exact date or time for when the rapture will happen. However, it describes the event in passages like 1 Thessalonians 4:15-17, where believers who are alive and those who have died will be caught up together to meet the Lord in the air at His coming. The timing of the rapture is debated among Christians, with some believing it will happen before the tribulation (pre-tribulation), some at the midpoint (mid-tribulation), and others at the end of the tribulation period (post-tribulation).
Jesus himself said no one knows the day or hour of His coming, emphasizing the uncertainty of the exact timing (Matthew 24:36). The rapture is associated with the return or "parousia" of Christ, but interpretations vary on its relationship with other end-times events such as the tribulation and the Day of the Lord.
In summary, the Bible indicates the rapture will happen at the coming of the Lord but does not give a specific date or time, and different Christian traditions interpret its timing relative to the tribulation in various ways.