Erik Manning recently wrote a blog post arguing for a pre-70 date for the canonical gospels. I wrote up some thoughts in a Facebook comment responding to a query about the post, and I thought I'd make those thoughts (and a couple others) available here.
1) Manning seems to refer to all dates for the gospels after 70 as "late." The implication is that pre-70 dates are "early." I don't think this is a particularly helpful typology. There is surely a significant difference between someone who dates Luke's Gospel c. 80 and someone who dates Luke's Gospel c. 120. I prefer to use a typology of "lower" (pre-70), "middle" (between 70 and 100), and "higher" (after 100), as this allows us to differentiate more fully between the majority position within scholarship (which is for the most part a "middle" chronology, on this typology) and the minorities who hold respectively to "lower" and a "higher" ones.
2) Manning's evaluation of post-70 dates is a bit of a straw man. He suggests that the only thing going for such dates is the denial of the supernatural. His reasoning goes like this: Jesus predicted the fate of the temple; scholars who "rule out" the supernatural deny that he could have done so pre-70; therefore such scholars conclude that the gospels must post-date 70. Moreover, he argues, this is the only reason to affirm a post-70 date for the canonical gospels. This is a straw man in at least two regards. First, while the canonical gospels' treatment of the temple's fate is probably the single strongest argument in favour of a post-70 date for each of the gospels, it is hardly the only one. Second, there are scholars who "rule out the supernatural" yet affirm that at least one canonical gospel predates 70. This is because one need not believe in the supernatural to believe that Jesus could have anticipated the destruction or desecration of the temple (both anticipations appear in the gospel tradition). It's entirely plausible that someone writing before 70, familiar with the various Jewish writings that talk about the destruction of the first temple and the desecration of the second under Antiochus IV, could think that perhaps one day the temple might be destroyed or desecrated. And I'd add moreover that a pre-70 date for one or more of the gospels does not require one to affirm that Jesus anticipated either the temple's destruction or desecration, merely that someone (whether Jesus, a tradent operating after Jesus, or the evangelists themselves) operating prior to 70 could have anticipated such. Cultural hand wringing about the supernatural is entirely a red herring.
4) Let us now consider Manning's seven reasons, enumerating them by Roman numerals.
i) Manning notes that Paul is still alive and well at the end of Acts. (He incorrectly states that Paul was under house arrest in Malta. The house arrest is actually and famously in Rome). Of the different explanations for the ending of Acts, I still think that the strongest argument is that Acts ends where it does because Paul was yet alive when the book was written. I find it exegetically baffling that a full quarter of Acts is devoted to the legal and other processes that result with Paul pending trial in Rome, only for the book to end without any report upon how his legal case turns out. As such, I find it easier to read the ending of Acts sometime between 62 (the likely year in which the house arrest in Rome ended) and before 68 (the latest likely year of Paul's death) than I can after 68. One should however note that other explanations remains viable: just because I think this explanation the strongest does not demonstrate that the others must be wrong.