I just want to throw it out there as I've heard a different theory on the 2,300 days that is compelling from our history, Daniel's future, just under a couple hundred years before Christ. We see a series of animals and horns described visually and these are later interpreted for Daniel.
- Ram with 2 horns = 2 kings of Media and Persia (Medo-Persia)
- He Goat with notable horn = King of Greece (Alexander the Great)
- Four notable horns from the broken notable horn = four kingdoms arising out of it [Alexander's kingdom was split between his four generals]
- Seleucus I - Seleucid empire (Turkey to India)
- Cassander - Macedonia (Greece)
- Lysimachus - Thracia (between Turkey and Greece)
- Ptolemy I - (Egypt)
- Out of one of them a little horn waxes great and by him the daily sacrifice is taken away and the sanctuary cast down.
We're then told it will be trodden under foot for 2,300 evenings (ereb) and mornings (boqer) (translated days), then the sanctuary will be cleansed. Daniel is told this will be for a "time at the end" and "in the last end of the indignation for the time appointed the end shall be." However, the definitions for these fit into our historical record amazingly well. It may be that time at the end is from Daniel's perspective just before the first 69 weeks would be fulfilled and the Messiah arrives.
Verse 23 interprets the time of this little horn "in the latter time of their kingdom," being the four kingdoms that rise up from Alexander the Great. This king of fierce countenance destroys the mighty and holy people. This is the one who stops the daily sacrifice and casts down the sanctuary. We have this character too from history, Antiochus Epiphanes IV, who stopped the daily sacrifice and setup an idol in the temple for the Jews to worship. This abomination of desolation in 167 BC triggered the Maccabean revolt.
So how does the 2,300 days fit into this? I can't explain it better than the site below. Basically, on a 360-day calendar used historically, and counting the evening and morning sacrifices, and the detailed accounts of when the stopping of the daily sacrifice (I Maccabees 1:54) and starting back up were (I Maccabees 4:52-53), there were 1,150 evenings and 1,150 mornings for a total of 2,300 between those times. Chanukah was instituted from this time at the end when the temple was rededicated!
So the two saints talking, answering the question "How long shall be the vision concerning the daily sacrifice, and the transgression of desolation, to give both the sanctuary and the host to be trodden under foot?" is answered in context of the daily sacrifice that was stopped and since the daily sacrifice consists of a morning and evening sacrifice, that was the number of ereb boqer until the sanctuary was cleansed.
The site is no longer up, but thanks to the Wayback Machine it's still accessible:
https://web.archive.org/web/20220219045008/http://moellerhaus.com/2300.htm
This isn't to say there is no possible future echo of this, as we saw with Antiochus, he was a kind of foreshadow of the man of sin yet to come. I just wanted to throw in the historical perspective of the 2,300 days for those who may not have heard it before because I think it's an amazing testimony of prophecy.