Robert said
She also makes the point that the local pagan communities and Roman authorities would have been opposed to the atheistic denial of all the polytheistic gods.
  

I forget who first made the analogy but someone suggested that pagans viewed Christians the same way modern Americans view groups like the Jehovah's Witnesses, who don't celebrate Christmas and refuse to recite the Pledge of Allegiance.  You know, weirdos. Of course Rome did not enjoy Freedom of Religion and their judicial system rewarded a disturbingly long list of infractions with the Death Penalty.

Dan Schmidt, an Assembly of God pastor and member of the Batavia City Schools board in New York, cast the lone vote against a senior class trip because students wanted to visit the Salem Witch Museum.  

Schmidt called it a “Satanic" museum, urged “the church” to protest, and claimed Jesus would disapprove—even though the museum actually teaches visitors about the Salem witch trials and the persecution of innocent people.

Schmidt later admitted “I can’t really say that I know the history of it.” 

Allow me to wholeheartedly recommend Hemant Mehta's YouTube channel, The Friendly Atheist. He is.  (Like me.) What sets him off is not religion per se but church/state separation issues. (Like me.)  Mehta has a healthy sense of humor and is aware of what deserves mockery and what is worthy of criticism. (Like me.) If I was going to create an "Atheist" YT channel this most nearly resembles what I would shoot for. But Mehta does it so I don't have to.

Helen Young said 
But we both do agree, according to his authentic letters, that Paul did persecute them. Correct?

Sure, but I doubt there was much violence or imprisonment involved. We do know, however, that Paul was inclined toward combative and passionate argumentation, probably not very pleasant at all 

Stephen said
I flip back and forth on how large the Jesus community was by time of the Crucifixion.  The gospels exaggerate but Prof Ehrman's "twenty guys in a room" raises a lot of questions too.  We know there were still Jewish Jesus sectarians in the second century. They came from somewhere.
Perhaps we should imagine a substantial Jesus community left behind in the Galilee when Jesus went to Jerusalem. Perhaps the success of that community was part of the motivation to go to Jerusalem? This would also explain how Paul could encounter Jesus sectarians in Damascus so soon after Jesus death.
  

I'm on board with the possibly substantial community in Galilee and perhaps some in Damascus within a few years. When Paul was persecuting believers in mostly Greek-speaking (?) synagogues about that time, I think there were probably not that many believers to yet be perceived as a threat to the Judean authorities or in diaspora synagogues. By the late 40s, there were public disputes in Rome about 'Chrestus' that did require the attention of Suetonius and a similar account by Cassius Dio. 

Robert said
Given the much more direct evidence from Paul's authentic letters and the notoriously unreliable accounts in Acts, I would say it's virtually impossible for me to ever be certain that Paul imprisoned Christians.
  

But we both do agree, according to his authentic letters, that Paul did persecute them. Correct?

I flip back and forth on how large the Jesus community was by time of the Crucifixion.  The gospels exaggerate but Prof Ehrman's "twenty guys in a room" raises a lot of questions too.  We know there were still Jewish Jesus sectarians in the second century. They came from somewhere. 

Perhaps we should imagine a substantial Jesus community left behind in the Galilee when Jesus went to Jerusalem. Perhaps the success of that community was part of the motivation to go to Jerusalem? This would also explain how Paul could encounter Jesus sectarians in Damascus so soon after Jesus death. 

Robert said
I see no reason to make that assumption. He does speak about being more advanced in his Judean zeal for the Law and the traditions of the Pharisees, especially exceeding others in his persecution of the believers in Christ: (Phlpn 3,4b–6 Gal 1,13–14):

If anyone else has reason to be confident in the flesh, I have more: circumcised on the eighth day, a member of the people of Israel, of the tribe of Benjamin, a Hebrew born of Hebrews; as to the law, a Pharisee; as to zeal, a persecutor of the church; as to righteousness under the law, blameless. ...
You have heard, no doubt, of my earlier life in Judaism. I was exceedingly persecuting the church of God and was trying to destroy it. I advanced in Judaism beyond many among my people of the same age, for I was far more zealous for the traditions of my ancestors.

This doesn't sound like Roman opposition to the fledgling Jewish believers in a crucified Messiah. It sounds like persecution based on his Jewish zeal.
  

I don't know if we can ever be positive that Paul was instrumental in having Christians imprisoned. Acts does say he was, however.

If anyone else has reason to be confident in the flesh, I have more: circumcised on the eighth day, a member of the people of Israel, of the tribe of Benjamin, a Hebrew born of Hebrews; as to the law, a Pharisee; as to zeal, a persecutor of the church; as to righteousness under the law, blameless. ...

You have heard, no doubt, of my earlier life in Judaism. I was exceedingly persecuting the church of God and was trying to destroy it. I advanced in Judaism beyond many among my people of the same age, for I was far more zealous for the traditions of my ancestors.

This doesn't sound like Roman opposition to the fledgling Jewish believers in a crucified Messiah. It sounds like persecution based on his Jewish zeal.

Robert said
Paul does mention having been imprisoned, but that is not one of the Jewish punishments he received (2 Cor 11,24–25):

Five times I received from the Jews the forty lashes minus one. Three times I was beaten with rods, once I was pelted with stones ... 

Imprisonment typically would have been done by Roman authorities. 
  

Acts states that Saul/Paul was imprisoning Christians. Can we consider him one of the Roman authorities at this time, or working in connection with Roman authorities?

Acts 8:3

New International Version
But Saul began to destroy the church. Going from house to house, he dragged off both men and women and put them in prison.

Five times I received from the Jews the forty lashes minus one. Three times I was beaten with rods, once I was pelted with stones ... 

Imprisonment typically would have been done by Roman authorities. 

Robert said
Why do you think these quotes imply that Paul sought to imprison Christians?
  

Isn't that what they were doing to the Christians? Or is that only in Acts also?