Paul explains the “times and the seasons” (I Thess. 5:1) of the catching up (I Thess. ) as the “day of the Lord” (5:2) which FOLLOWS the posttrib sun/moon darkening (Matt. 24:29; Acts ) WHEN “sudden destruction” (5:3) of the wicked occurs! The "rest" for "all them that believe" is also tied to such destruction in II Thess. 1:6-10! (If the wicked are destroyed before or during the trib, who'd be left alive to serve the Antichrist?) Paul also ties the change-into-immortality “rapture” (I Cor. ) to the end of trib “death” ( ). (Will death be ended before or during the trib? Of course not! And vs. 54 is also tied to Isa. 25:8 which Scofield views as Israel's posttrib resurrection!) It's amazing that the Olivet Discourse contains the "great commission" for the church but not even a hint of a pretrib rapture for the church!
Many don't know that before 1830 all Christians had always viewed I Thess. 4’s “catching up” as an integral part of the final second coming to earth. In 1830 this "rapture" was stretched forward and turned into an idolized separate coming of Christ. To further strengthen their novel view, which evangelical scholars overwhelmingly rejected throughout the 1800s, pretrib teachers in the early 1900s began to stretch forward the “day of the Lord” (what Darby and Scofield never dared to do) and hook it up with their already-stretched-forward “rapture.” Many leading evangelical scholars still weren’t convinced of pretrib, so pretrib teachers then began teaching that the “falling away” of II Thess. 2:3 is really a pretrib rapture (the same as saying that the “rapture” in 2:3 must happen before the “rapture” ["gathering"] in 2:1 can happen – the height of desperation!). Google "Walvoord Melts Ice" for more on this, and also Google "Pretrib Rapture Pride."
And if you would like to see two excellent works proving how unbiblical the pretrib rapture really is, I am happy to recommend "The End Times Passover" and "Why Christians Will Suffer Great Tribulation," both by my good friend Joe Ortiz (Google "Joe Ortiz Associates").