Easton's Bible Dictionary

Libertine - found only Acts 6:9, one who once had been a slave, but who had been set at liberty, or the child of such a person. In this case the name probably denotes those descendants of Jews who had been carried captives to Rome as prisoners of war by Pompey and other Roman generals in the Syrian wars, and had afterwards been liberated. In A.D. 19 these manumitted Jews were banished from Rome. Many of them found their way to Jerusalem, and there established a synagogue.