It is important to compare and contrast the Gospels whenever an event is described by more than one author. In the case of Mark 13, we have both Matthew and Luke describing a very similar event with a few clear differences. Matt and Mark are private discussions with his disciples on the mount of olives but Luke 21 describes Yehoshua teaching in the temple to the people. Verse 5 “And as some were speaking about the Set-apart Place, that it was adorned with goodly stones and gifts, He said,”
In verse 12 Luke begins a discussion that describes the destruction of Jerusalem in 70 AD, the dispersion of the Jews into all nations and later the end-times. The abomination of desolation is absent from Luke’s account, but present in Matt 24 and Mark 13.
When we examine Luke’s account more deeply, it is unclear if Yehoshua is really addressing the crowds. The disciples’ comments in verse 5 parallel Matt 24:1 and Mark 13:1 and likewise prompted a similar response from Yehoshua.
The four disciples that approached Him privately on the Mt. of Olives asked him three questions after He foretold the destruction of the Temple to the last stone:
1) When will it happen,
2) what will be the sign of your coming, and
3) what will be the sign of the end of the age? Matt 24:3
In Matt and Mark, Yehoshua address the 2nd and 3rd questions but in Luke He also answers the first, and does so in chapter 21 verses 12-24. Beginning in verse 25 the end times is in view again.