The seven year great tribulation, which is not found anywhere in scripture, was derived by mans misinterpretation of Daniel 9:24-27.
I will reiterate what I believe on Daniel's 70th Week. I've probably shared on this a number of times, but it's my only answer to this difficult passage, which I've struggled with for many years. I don't struggle so much now because after going from school to school and from position to position I finally have an assortment that at least makes sense as a whole. Not saying I'm right....
Daniel is concerned about the restoration of the temple worship after the Babylonian Captivity ends. And an angel shows him that the temple will be restored, but will be destroyed yet again in the time of Messiah. It is the prince of the 4th Kingdom, I believe, whose people, a Roman army, will destroy Jerusalem and the temple.
This army is identified as an "abomination that causes desolation." This begins a period of trouble for Israel identified as the "great tribulation." Jesus later indicated this destruction of Jerusalem and the temple would lead to an age-long exile of the Jewish People, now called the "Jewish Diaspora."
Luke describes a "Jewish Punishment" that comes upon Israel for persecuting Christ and his Disciples, that causes Israel to lose their homeland and their Covenant with God. But it also causes suffering for Christians who like Christ are persecuted by Jews and Gentiles alike.
This is the actual "Great Tribulation"--not the one we hear about all the time in connection with the Antichrist. That is yet another Great Tribulation of sorts, but which actually is just a continuation of the same Great Tribulation we've had for the Jews and for fallen Christians nations for centuries.
From the time of Artaxerxes' decree in 457 BC to 26 AD is 483 years, or "69 Weeks," leaving the 70th Week remaining. I believe that instead of the 70th Week being a full Week, it actually ended in a Half-Week when Christ was put to death.
That is when the Roman ruler, by putting Christ to death, terminated the usefulness of animal sacrifices and offerings under the Law. The temple veil had been rent, signifying that the covenant of Law had been broken.
So the 70 Weeks Prophecy was fulfilled in history, with the exception that the prophecy indicated the 70 Week period would be followed by the destruction of Jerusalem and the temple by the same ruler who put Jesus to death. It was the same Roman ruler who indirectly causes sacrifices and offerings to cease under the Law by removing the one to whom they had been offered.
Anybody curious about my position, this is it.