TEN DETAILED CHAPTERS answering this very debated topic.   
 
When will the church be raptured ?  Before the tribulation, midway through or at the end ?
 
Gary L Cox does a "deep dive" covering the:
 
Purpose of the Tribulation
Promises to the Church to Escape the Tribulation
Posture of the Apostles and Early Church Concerning the Tribulation
Partitions of the Book of Revelation
Prevention of the AntiChrist Appearance
Problematic Differences Between the Rapture and Second Advent
Persons of the Twenty Four Elders and How They Prove the Church Will Be Raptured Pre-Tribulation
Participants in the Tribulation
Problem of Comfort Concerning the Church at Thessalonica