The Hellenist Messianic Jews were scattered abroad going into regions of Samaria and Judea (Acts 8:1) and then to more distant lands such as Phoenicia, Cyprus, Cyrene and Antioch (Acts 11:19-20). Paul pursued them to wherever it became known they were (Acts 26:11). In order for Paul to pursue the Hellenistic Messianic Jews to foreign cities, two things are implied. First, letters had to have been sent out from Jerusalem to those synagogues outside Judea to beware of this Messianic sect that had so little regard for the Temple, meaning the name of God (cp. Acts 28:21). Secondly, it would have to be known by those in Jerusalem that wanted Messianic Jews had traveled to such cities. Otherwise it would be like looking for the proverbial needle in a haystack. Therefore, news had to have been brought back to Jerusalem such cities alerting the high priest that these Messianic Jews had come there and were spreading the Gospel in their synagogues (Acts 26:11), before someone such as Saul would journey there.
Some time must be presumed to have elapsed to allow for such communication. Acts 9:1 shows Paul seeking letters of extradition from the high priest. If Stephen was stoned in 34 CE about the time of the fall Holy Days, then a reasonable period for word to be brought back from Damascus to the Jerusalem authorities concerning the Messianic believers there would be the next celebration of a major Jewish Holy Day season. This would be in the spring during the Passover of 35 CE. At the time of this particular Passover Caiaphas, the high priest, was removed from his office by Vitellius, the new Roman governor of Syria, and Jonathan, the son of Annas, was placed in that position. Later, Paul would refer to Jonathan who reigned as high priest a second time during the time of Felix’s tenure (see Acts 22:5). The reason for Paul’s mentioning the high priest at that time was that he could verify that he had been sent by him to incarcerate believers at Damascus and bring them to Jerusalem for punishment.
Therefore, Acts 9:1 denotes the passage of time of about six months from the time of Stephen’s stoning. If this is logically sound, then we can also point to 35 CE as the year of Paul conversion backward from the Jerusalem Council which most scholars believe occurred in 49 CE. This was the visit Paul himself referred to in Galatians 2:1 his second visit after his meeting Jesus. Fourteen years after 35 CE would bring us to the time of the Jerusalem Council.
Additionally, we can reasonably point to the 35 CE date by calculating a pattern Paul seems to use in his ministry. He seems to spend about 3 years working in a given area founding churches in a given locale in Jesus name. We know he spent three years in Damascus with excursions into Arabia (Galatians 1:15-18). If Paul returned to Jerusalem in 38 CE, but had to leave for Cilicia not long afterward, we can reasonably assume he spent another three years evangelizing Tarsus and surrounding communities, because Barnabas sought him out for the work at Antioch about the time Claudius Caesar became Emperor in 41 CE (Acts 11:25-28). Luke tells us that he an Barnabas taught the new gentile believers for a full year (Acts 11:26), but this doesn’t mean they wouldn’t spend another two years preaching Christ in the surrounding communities of Phoenicia, Samaria and Galilee (Acts 26:20), thus, reasonably keeping within his three year plan. Then in the spring of 44 CE Paul and Barnabas went on the evangelistic labor for another three years in Galatia before returning to Antioch about the spring of 47 CE where Luke says they spent a good while (Acts 14:26-28).
If they spent another three years here before leaving to check on the churches in Galatia (Acts 15:35-36), this would bring them to the spring of 50 CE. This is a full year after the Jerusalem Council of 49 CE. If this is logically sound according to the pattern Paul seems to use throughout his ministry, then this also points to 35 CE as the year of Paul’s vision of Jesus and becoming a believer. Therefore, it is my opinion that Paul persecuted the Church for about six months—from the autumn of 34 CE to the spring of 35 CE.
 This post is a revision both in the time I presume Paul persecuted believers and in the manner in which I calculated that time. I came to realize my previous post had too many errors in it to permit it to remain published, so I revised it as best as I understand the truth.