5:1–11 The Thessalonians are told to prepare for the same thing that will come unexpectedly upon the ungodly—the day of the Lord (vv. 2, 4). Paul assumes that Christians and non-Christians alike will be alive and present when the Day arrives, Christians watchful and ready, non-Christians surprised as by a thief who comes at night. In other words, the rapture of Christians spoken of in 4:17 will not occur before the arrival of the Day that will also bring sudden and inescapable destruction to the wicked (2 Thess. 2:1, 2 notes). See “The Return of Jesus Christ” at 4:16.