An interesting argument in behalf of the pre-Tribulation timing of the Rapture can be found in 2 Thessalonians. The church at Thessalonica was in a turmoil because someone had written them a letter under Paul's name stating that they had missed the "gathering to the Lord" and were, in fact, living in "the day of the Lord" (2 Thessalonians 2:1-2).
Paul attempted to calm them down by reminding them of his teaching that the day of the Lord would not come until after the Antichrist is revealed. He then stated that the Antichrist would not be revealed until a restraining force "is taken out of the way" (2 Thessalonians 2:3-7).
There has been much speculation as to the identity of this restraining force that Paul refers to. Some have identified it as the Holy Spirit. But it cannot be the Holy Spirit because there will be people saved during the Tribulation, and no one can be saved apart from the testimony of the Spirit (John 16:8-11 & 1 John 5:7).
Others have identified the restrainer as human government. It is true that government was ordained by God to restrain evil (Romans 13:1-4). But the governments of the world are in rebellion against God and His Son (Psalm 2), and they are therefore a contributor to the evil that characterizes the world. Furthermore, the Tribulation will not be characterized by a lack of government. Rather, it will feature the first true worldwide government (Revelation 13:7).
In my opinion that leaves only one other candidate for Paul's restrainer - and that is the Church. It is the Church that serves as the primary restrainer of evil in the world today as it proclaims the Gospel and stands for righteousness. When the Church fails in this mission, evil multiplies, as Paul graphically points out in 2 Timothy 3:1-5. Paul says that society in the end times will be characterized by chaos and despair because "men will hold to a form of religion but will deny its power." When the Church is removed from the world, all hell will literally break loose.