There are definitely some notable differences between Luke 21 and the other accounts. This gives rise to many unnecessary controversies and erroneous interpretations and conclusions. I urge everyone to review this video which maps out the differences.
Well at 2:30 is where he makes a case that Luke and Matthew are speaking about two different events. But he makes a mistake. Notice what's said...
Matthew 24-4-16 (listed):
- Deception
- Wars
- Famines
- Earthquakes
- Persecution/death of "them" (His disciples) for their testimony
- Lack of brotherly love
-
The abomination of DESOLATION; Flee to mountains!
- Time of Great Tribulation begins
- Days cut short because of the elect
- Fearful events & signs from heaven
Mark 13-4-16 (listed):
- Deception
- Wars
- Earthquakes
- Famines
- Persecution/death of "them" (His disciples) for their testimony
- Lack of brotherly love
-
The abomination of DESOLATION; Flee to mountains!
- Days of Tribulation begins
- Days cut short because of the elect
- Fearful events & signs from heaven
Luke 21:8-21 (listed):
- Deception
- Wars
- Earthquakes
- Famines
- Pestilences (diseases)
- Fearful events & signs from heaven ("
but before this")
- Persecution/death of "them" (His disciples) for their testimony
- Betrayal of kin
-
Jerusalem surrounded by armies, know that its DESTRUCTION is near; Flee to mountains!
- Time of Great Tribulation begins (lit.
wrath against these people; Jews) until time of gentiles fulfilled
- Fearful events & signs from heaven (
mentioned again)
-----------
So it was the "fearful events & signs from heaven" that were mentioned early in Luke. Aside from that, everything else in Luke's account lines up with the other two accounts. Testimony of two or more establishes truth, so we have to rely on Matthew & Mark as the foundation for the sequence to confirm Luke's account.