A Jew is a descendant of Abraham, Isaac, and Jacob. A Roman is an Italian of the city of Rome. However, as Rome became the dominant city in the world, especially during the lifetime of Paul, the term "Roman" applied not only to one whose birthplace was Rome but also to select individuals of the Roman Empire. To be a Roman citizen was considered an extremely valuable asset.
In Paul's day Roman citizenship was relatively rare and was awarded to those non-residents of Rome who had performed some notable service to the Empire or who had paid a very high price to obtain it. That citizenship could be passed down to one's descendants. So Paul inherited his citizenship from his father. That indicates that he must have been from a very wealthy and influential family because, although Jewish and born in the province of Cilicia, in what is now the south-east coast of modern Turkey, his father or grandfather must have done something remarkable to be granted this title of Citizen of Rome. This citizenship conferred certain privileges such as freedom from taxation and the right to appeal one's case in legal mattes all the way to the Emperor himself. If a Roman citizen were convicted of a capital crime, he could not be crucified or tortured but must have a "clean" death, usually beheading.
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