I'm now over 50,000 words and ready to seal up my Acts book. This is from the last chapter.
It makes a significant difference to the way we understand Luke’s indictment of the Jews if he wrote Acts after Jerusalem and its temple was destroyed. It is no secret that many individuals in history, calling themselves Christians, have justified persecuting the Jews in the name of God and the Bible. Even today, many Christians think that the ending of Acts signaled the end of Israel as God’s people.
On the other hand, if Acts was written after the destruction of Jerusalem, it takes on a quite different connotation. Now, Luke’s readers can see clearly in hindsight why God allowed Jerusalem to be destroyed. They had turned away from his plan. He brought the Messiah into the world and they rejected the good news. So God turned to the Gentiles for a season.
Luke 21:24 gives us a peak into what Luke was thinking. Luke 21 gives us Jesus’ prediction that the Jerusalem temple was going to be destroyed, something that happened in AD70. In Matthew and Mark, we have the prediction in its raw form—Jesus warns his followers to flee to the mountains when they see the “abomination that causes desolation standing where it does not belong” (Mark 13:14).
Arguably, Luke paraphrases this prediction with all the benefit of hindsight: “When you see Jerusalem being surrounded by armies, you will know that its desolation is near” (Luke 21:20). Luke makes it clear to his audience what Jesus’ more ambiguously worded prediction meant. 
One element of Luke’s clarification is striking. The Jews of Jerusalem will be taken as prisoners to all the nations (21:24). Then “Jerusalem will be trampled on by the Gentiles until the times of the Gentiles are fulfilled.” Here we have the key to Luke’s thinking. We live in the times of the Gentiles. God was going to turn away from the Jews for a season.
But there is an “until” in Luke’s inspired understanding. It is not a permanent turning away. Luke’s thinking here is presumably similar to Paul’s in Romans 11. For a season, God has cut out the natural branches of his tree, unbelieving Israel. “Israel has experienced a hardening in part until the full number of the Gentiles has come in” (Rom. 11:25).
Many translations then botch the next verse, in my opinion, because Paul is contrasting the “part” that is now hardened with what will take place around the time of Jesus’ return. “So all Israel will be saved” (11:26, NASB). Paul says that God’s “call is irrevocable” (11:29), so God will not abandon the Jews forever. Those he has currently surrendered to disobedience will eventually receive mercy (11:31-32).
It is very important to keep this overall perspective in mind when we read about the Jews in Acts. Otherwise, we will get the sense that Acts is telling us how to behave toward Jews today, when in fact Acts is explaining why certain events happened to Jews in the past.
 We should not be troubled at all that Luke would paraphrase Mark’s words. This sort of editing was completely acceptable in Luke’s day. God originally inspired Luke-Acts to speak to them in their categories, not to conform to our expectations today.