Given the time he spent in Jerusalem before his conversion, there must surely have been believers in Judea that knew Paul personally. Paul does not deny this reality when he says he was unknown to the churches. What he means is that the majority of believers in that province/area did not know him personally.1 Most of what they knew about him came from what they heard others say. He did not appear in their assemblies as a preacher of the gospel.2 Paul mentions this to make it clear that he did not receive a missionary commission from the Jerusalem apostles, Judea presumably being the area he would have worked in if he did.3
22 And I was still unknown in person to the churches of Judea that are in Christ.