Liberal and skeptical scholars have long noted that Jesus’ prediction of the destruction of Jerusalem in Luke 19:42-44 prove that the Gospel according to Luke must have been written after AD 70. How else, they argue, could the writer of the Gospel known about the Roman siege and destruction of Jerusalem? In fact, since most scholars believe Mark was the first gospel written, and Mark also mentions the destruction of Jerusalem, then all the gospels must have been written after AD 70.
Fr. Dwight Longenecker, writing at Catholic Answers, frames the issue this way:
With their rationalist presuppositions firmly in place, modern biblical critics concluded that the entire New Testament could not have been composed before the year 70. The reasoning went like this: ‘Mark’s Gospel is the earliest Gospel. Jesus predicted the destruction of Jerusalem. We know that people can’t foretell the future. Therefore this must have been written after the event and made to sound like a prophecy.’ This one conclusion—based on the assumption that seeing the future is impossible—is the basis for the continuing idea that the New Testament is a late-invented document.
Once this ‘fact’ was in place, every other piece of evidence relating to the dating of the Gospels had to conform to this single conclusion. So, if evidence was found that a particular Gospel was written earlier than A.D. 70, it could not be so, because everyone ‘knew’ that it all had to be written after A.D. 70. The authorship of the Gospels also had to be in question. If most the apostles died before A.D. 70, then it was impossible for them to be the authors of the Gospels.
What the critics fail to understand is that there are at least two other possibilities. First, Jesus may have been making an educated guess that Jerusalem would be destroyed due to her rebellious tendencies. The description of the siege in Luke 19 is applicable to almost any siege of a major city in the ancient near east.
Second, and more likely, Jesus was making a supernatural prediction. He could have had a supernatural vision of the destruction of Jerusalem which he then reported to his disciples, who then wrote the prediction down.
The only way critics can dismiss this second possibility is to deny the possibility that Jesus was given a vision of the future. But how can they possibly know that Jesus could not have received a vision from God? They cannot.
For many critical scholars, it is a philosophical presupposition that miracles cannot occur, that the supernatural does not exist, that a Creator God does not exist (i.e., that theism is false). But if a Creator God who interacts with the universe He created does exist, then it is entirely possible that Jesus received a vision from that God. Jesus repeatedly claimed to be an emissary from God, to have a special relationship with God, so if anyone was going to receive knowledge of future events, it would be Jesus.
In brief, the gospels cannot be dated by first assuming that theism is false. If there are good reasons to believe that theism is true (and there are many), miracles are possible. Since the New Testament is full of miracles, a scholar looking to date the NT documents simply cannot ignore the possibility that at least some of the miracles recorded actually did occur.