Bart Ehrman’s post, Oral Traditions and the Dates of Our Gospels, October 23, 2024, provides extracts from the 8th edition of his textbook The New Testament: A Historical Introduction to the New Testament (Oxford University Press, 2024), Below are extracts from the post that provides basic reasons for the traditional dates of when the Gospels were written. Underline and bold emphasis is mine.
Critical scholars are widely agreed that the earliest Gospel was Mark, written around 70 CE; that Matthew and Luke were some years later, say, 80-85 CE; and that John was the last Gospel, around 90-95 CE. But how do scholars establish those dates?
To begin with, none of the Gospels appears to have been known to the apostle Paul, writing in the 50s. Paul was an extraordinarily well-traveled and well-connected apostle, as we will see, and if anyone would have known about the existence of written accounts of Jesus’ life, it would have been him. Probably they did not exist yet. *
On the other hand, early non-canonical authors such as Ignatius of Antioch and Polycarp of Smyrna (see chapter 28) do seem to know some of the Gospels. And so some or all of the Gospels were written before these authors produced their letters, around 110-15 CE. This means that the Gospels probably date to somewhere between 60-115.
It is frequently noted that the earliest Gospels seem to presuppose the destruction of the city of Jerusalem and of the Jewish temple, as happened in 70 CE. And so, for example, in Mark’s Gospel Jesus indicates that the nation of Israel will be destroyed (Mark 12:9) and that the temple will not be left standing (Mark 13:1-2). Matthew is even more explicit: here Jesus tells a parable in which God is portrayed as burning the city and killing its inhabitants (Matt 22:8). Luke has similar passages (e.g., Luke 21:24). All these passages seem to presuppose that by the time the books were written, the destruction had happened.
Someone may respond by saying that in these passages Jesus is predicting the destruction of the Jerusalem, not looking back on it. Fair enough! But when is a Christian author likely to record a prediction of Jesus in order to show that he predicted something accurately? Obviously, in order to show that Jesus knew what he was talking about, an author would want to write about these predictions only after they had been fulfilled.
‘* My thoughts – Paul’s letters clearly argued against anyone who disagreed with his “Gospel”. If he had read or heard about the four Gospels then he would have warned his followers to disregard at least parts of all of them.