The Greek text of this verse reads: or in English: The meaning of Libertine in this passage is different from the generally understood connotation of "a dissolute person".
The probability is that there are three, corresponding to the geographical regions involved, Rome and Italy, Northeast Africa, and Anatolia.
In this case, the Synagogue of the Libertines is the assembly of the Freedmen from Rome, descendants of the Jews enslaved by Pompey after his conquest of Judea in 63 BC.
The obscure town Libertum inferred from the title Episcopus Libertinensis in connection with the synod of Carthage, AD 411 is less likely than the reading λιβιων underlying certain Armenian versions and Syriac commentaries.
Consequently, these returned Jews, instead of being liberalized by their residence abroad, were more tenacious of Judaism and more bitter against Stephen than those who had never left Judaea.