But we don't want you to be ignorant, brothers, concerning those who have fallen asleep, so that you don't grieve like the rest, who have no hope.
Pretribulationists and posttribulationists agree that the Thessalonian believers were grieving for two reasons. They grieved because their loved ones had died and because they thought the resurrection of dead Christians would take place after the Rapture. Pretribulationists believe the Thessalonians erroneously thought this resurrection would follow the Tribulation. Some posttribulationists believe the Thessalonians incorrectly thought that this resurrection would take place at the end of the Millennium. [Note: E.g., Robert Gundry, The Church and the Tribulation, p. 101.] Both of these conclusions rest on the interpretation of other passages that indicate the time of the Rapture. It was not the resurrection as such that disturbed the Thessalonians but the fact that they might not see their departed brethren for a long time that did. Specifically it was the fact that their dead fellow Christians might not participate in the Rapture with them that upset them. They apparently thought that one had to be alive to participate in the Rapture. [Note: Wanamaker, pp. 169, 172. See also Joseph Plevnik, "The Taking Up of the Faithful and the Resurrection of the Dead in 1 Thessalonians 4:13-18," Catholic Biblical Quarterly 46 (1984):281.] 