So where does Scripture tell us that weeks mean years?
Let's look at this question, while the bible doesn't say that these weeks mean years, if it is taken as literal weeks we can look at how how it was to be fulfilled.
First look at Daniel 9:24 Seventy weeks are determined upon thy people and upon thy holy city, to finish the transgression, and to make an end of sins, and to make reconciliation for iniquity, and to bring in everlasting righteousness, and to seal up the vision and prophecy, and to anoint the most Holy.
25 Know therefore and understand, that from the going forth of the commandment to restore and to build Jerusalem unto the Messiah the Prince shall be seven weeks, and threescore and two weeks: the street shall be built again, and the wall, even in troublous times.
26 And after threescore and two weeks shall Messiah be cut off, but not for himself: and the people of the prince that shall come shall destroy the city and the sanctuary; and the end thereof shall be with a flood, and unto the end of the war desolations are determined.
27 And he shall confirm the covenant with many for one week: and in the midst of the week he shall cause the sacrifice and the oblation to cease, and for the overspreading of abominations he shall make it desolate, even until the consummation, and that determined shall be poured upon the desolate.
It would be fulfilled with the Messiah coming and being cut off, put to death. Let's look at it as weeks, 69 weeks after after the decree to restore and to build Jerusalem until the coming of the Messiah.
That decree occurred sometime around 456 or so before the birth of Christ. So 69 weeks, that would mean that taken as a literal week the Messiah would have about 453 or 455 years before the birth of Jesus. Therefore if we take this as literal weeks then Jesus would not be the Messiah. However, if we take the 70 weeks to mean 7 years for each week Jesus would have come 483 years after the decree was issued. We don't need to be told that weeks mean years, Jesus' being cut off as Messiah proves them to be.
If these were literal weeks then we need to be looking for a different Savior, a Different Messiah. That being so we would need to have seen the abomination of desolation set up in that same time and yet as seen in
Mark 13:14 But when ye shall see the abomination of desolation, spoken of by Daniel the prophet, standing where it ought not, (let him that readeth understand,) then let them that be in Judaea flee to the mountains:
Jesus said it hadn't occured but it would in the future. If you take the Prophecy of Daniel and use 7 years from the crucifixion that would not be 70 A.D. that would have been around 40 A.D. There must be a wedge driven in time, a wedge God didn't reveal to the Prophets, but knew beforehand He would do it. Thus we have the time in which we live and there is still seven years or the last week of Daniel's seventieth to be concluded. The book of Revelation reveals this in Chapters 6 - 19. One week is given by the Lord in confirming His covenant with Israel.
81 A.D. Domitian had become emperor, he was the emperor who exiled John to the Isle of Patmos. Early church historians say Domitian was the emperor who exiled John. Therefore the writer of Revelation wrote the book between 81 to 96 A.D. that would be after the 70 A.D. destruction of Jerusalem and his transcription of Jesus Revelation of yet future events.
Even men like Matthew Henry hold to the 95-96 A.D. writing of the book.
"The testimony of the Church Fathers is that the Revelation of Jesus Christ was written by John near the end of the reign of Domitian in AD 96. According to them, John was banished by Domitian to the lonely Isle of Patmos, a desolate Greek island in the Aegean Sea only 11 square miles in area. Victorinus, in his Commentary on the Apocolypse of the Blessed John, recorded that John labored in the mines of Patmos.
Although there are many indirect references to John being banished to Patmos under Domitian in the Church Fathers, there are also direct references to John’s banishment under Domitian. The earliest of these is that of Irenaeus (c. 130-202). He was bishop of Lyons in Gaul. In Against Heresies (A.D. 180-199), Book V, Chapter 30, we read:
We will not, however, incur the risk of pronouncing positively as to the name of Antichrist; for if it were necessary that his name should be distinctly revealed in this present time, it would have been announced by him who beheld the apocalyptic vision. For that was seen no very long time since, but almost in our day, towards the end of Domitian's reign.
The church historian Eusebius Pamphili was born about 260 and died before 341. Bishop of Cæsarea in Palestine, he is known as the "Father of Church History." Eusebius confirms the authenticity of the testimony of Irenaeus. In chapter 18, Book 3 of his Church History, we read:
"It is said that in this persecution the apostle and evangelist John, who was still alive, was condemned to dwell on the island of Patmos in consequence of his testimony to the divine word. Irenaeus, in the fifth book of his work Against Heresies, where he discusses the number of the name of Antichrist which is given in the so-called Apocalypse of John, speaks as follows concerning him: a "If it were necessary for his name to be proclaimed openly at the present time, it would have been declared by him who saw the revelation. For it was seen not long ago, but almost in our own generation, at the end of the reign of Domitian."
So the book of Revelation would have been written after 70 A.D. according to these two well known early Christian writers. Therefore, Christ 1000 year reign had not occurred in the second or 4th century. So where do you find early church historians who back up your teaching of the 70 A.D. Kingdom of Christ. That they were looking for a literal anti-christ yet to come and the 1000 year reign of Christ.