But Saul laid waste the church, entering into every house, and dragging men and women committed them to prison. (ASV)
Saul is rampaging through Jerusalem "ravaging the church". However, Paul states himself in Galatians 1:22 that he was "unknown in person to the churches of Judea". Paul says that people had only heard of his persecutions in Judea, so the persecutions they heard must have occurred outside of Judea and Jerusalem.
In Acts 8 we are told:
1 Now Saul was consenting to his death. At that time a great persecution arose against the church which was at Jerusalem; and they were all scattered throughout the regions of Judea and Samaria,...
The persecution that Paul led was confined to the city of Jerusalem. As a result of that persecution, believers fled to the regions of Judea and Samaria as they were near Jerusalem and established churches in those regions. So, when Paul says in Galatians that he was unknown in person to the churches in Judea, he is referring to churches outside Jerusalem. The new believers in the churches in Judea, but outside Jerusalem, had not seen him in person as Paul was only persecuting those who resided in Jerusalem.
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