The fundamental problem with “left behind” theology is it is demonic. Darby (the Darby Bible, Plymouth Brethren, Biblical map of history, etc) was not Christian in any normal sense. He was steeped in pitch and brimstone, both fiery. He construed creation as the seat of evil and release from the world as salvation. Not Biblical.
Christ returns to reign on earth. Those who are left behind will be with Christ. Those who are taken will be in perpetual darkness. That is Biblical and consistent with Jesus’ teachings.
The “rapture” stuff did not really come out until the 18-19th centuries.
......”Those who are left behind will be with Christ. Those who are taken will be in perpetual darkness”......
What?......
Well there are ‘two’ comings....one ‘in the air’...the other Jesus’s ‘feet stand on the earth’.....
It’s written In Thess. 4....”we who are still alive and are left will be caught up together with them in the clouds to meet the Lord ‘in the air’.
and here...in Zechariah 14..... “In that day ‘His feet will stand’ on the Mount of Olives.
Neither of those accounts mention anything about those ‘taken’ being in darkness.