Tarsus was not a municipium, nor was it a colonia, like Philippi in Macedonia (Acts 16:12) or Antioch in Pisidia, but it was a "free city," like Syrian Antioch and its neighbor Seleucia. Such a city had the privilege of being governed by its own magistrates, and was exempted from the occupation of a Roman garrison, but its citizens did not necessarily possess the civitas of Rome.
Tarsus had received great benefits both from Julius Caesar and from Augustus, but the father of apostle Paul was not on that account a Roman citizen. This privilege had been granted to him, or had descended to him, as an individual right. He might have purchased it for a large sum of money (Acts 22:28). but it is more probable that it came to him as a reward of services rendered, during the civil wars, to some influential Roman.
In the language suggested by the narrative of Stephen's martyrdom (Acts 6:9), apostle Paul's father seems to have been a Cilician Libertinus. That Jews were not infrequently a citizen of Rome, we learn from Josephus, who mentions in the Jewish War book that some who were of the equestrian order were illegally scourged and crucified by Floras at Jerusalem. He also enumerates certain of his countrymen who possessed the Roman franchise at Ephesus in that important series of decrees relating to the Jews which were issued in the time of Julius Caesar.
The family of Paul were in the same position at Tarsus as those who were Jews of Asia Minor who were yet a Roman citizen at Ephesus. Thus, it came to pass, that while many of his contemporaries were willing to expend a large sum in the purchase of this freedom, the Apostle himself was free born.
Among those whom Paul calls his kinsmen in the Epistle to the church at Rome, two of the number, Junia and Lucius, have Roman names, while the others are Greek (Romans 16:7, 11, 21). All this may point to a strong Roman connection. These names may have something to do with that honorable citizenship which was an heirloom in the household. The appellation "Paulus" may be due to some such feelings as those which induced the historian Josephus to call himself "Flavius," in honor of Vespasian and the Flavian family.
The social position of Paul's father and family may not have been one of affluence and outward distinction. The civitas of the Roman empire, though at that time it could not be purchased without heavy expense, did not depend upon any conditions of wealth, where it was bestowed by authority. On the other hand, it is certain that the manual trade, which we know that Apostle Paul exercised, cannot be adduced as an argument to prove that his circumstances were narrow and mean.
It was a custom among the Jews that all boys should learn a trade. And if, in compliance with this good and useful custom of the Jews, the father of the young Cilician sought to make choice of a trade, which might fortify his son against idleness or against adversity, none would occur to him more naturally than the profitable occupation of the making of tents. The material used was hair-cloth, supplied by the goats of his native province, and sold in the markets of the Levant by the well-known name of cilicium.
The most reasonable conjecture is that Paul's father's business, as a citizen in the Roman Empire, was concerned with these markets, and that, like many of his scattered countrymen, he was actively occupied in the traffic of the Mediterranean coasts. The remote dispersion of those relations, whom he mentions in his letter from Corinth to Rome, is favorable to this opinion.