An Early Date for the Book of Acts: Great Post by Matt Slick of Christian Apologetics Research Ministry:
In determining the date of the book of Acts, what the author leaves out is very significant. In his brief history of the early church, he fails to mention Nero's persecution, the destruction of the temple in Jerusalem, and the final result of Paul's trials and the appeal's process.
This issue becomes even more striking since about a third of the book records events in Jerusalem, as well (relatively) minor persecutions. Furthermore, the end of Acts walks you through Paul's trials and all the places he goes in the appeals process. The author builds the story up to his final trial....but suddenly the story just stops and it has a kind of boring and awkward ending to be honest.
If you were writing a history of Christianity in China from 1940-1970, would you forget to mention how terrifying Mao's persecution was? Probably not.
Imagine someone documenting a major court case, with its appeals process, and even specific words made by the defense.......but not mentioning the supreme court decision on the matter.
Skeptics say that these are arguments from silence. They say that its fallacious to say that Luke's exclusion of these events entails that they didn't happen.
If the doctor knew you had a serious life-threatening illness but didn't tell you that you had it, would that be an argument from silence?
Yes and no.
The real argument is that any historian of Christianity is not going to leave out certain things since they are so important, especially if they record insignificant things by comparison. If it was minor events in the plot line of Acts, it would make sense to leave them out. However, the events Luke leaves out are sometimes more significant than the details he records. For example, he mentions a persecution in Jerusalem causing the scatter of Christians to Judea and Samaria, but makes no mention of Nero's persecution. Furthermore, he records certain of Paul's trials when they are less significant than his trial before Caesar....which he fails to mention.
Significance of an Early Date for Acts
If Acts was written before 64 A.D. (the Neronian Persecution), then that means Luke had to have been written before, since Acts is Part II of "Luke-Acts." This means Luke is written before Acts. But Mark has always been considered the earliest. The current theory with most acceptance among scholars is that Matthew and Luke depended on Mark for information. So this would mean Mark would be even earlier, possibly in the mid 50's.
This is problematic for non-Christian scholars for several reasons. First, it means that the likelihood that Luke actually knew eyewitnesses is much higher, because of the earlier date. Same applies to Mark. Furthermore, its much more difficult to claim legendary development with earlier sources like this, especially in ancient historical study. On top of all this, the probability of the traditional authorships of the Gospels becomes immensely more likely because of the earlier dates. Furthermore, with sources as early as this, its much more difficult to say that the disciples were claiming a non-bodily resurrection or vision as the basis for the resurrection appearances.