The Gemara tells of Mari bar Isak – a wealthy and powerful individual in Bavel – whose brother appeared having come from Bei Ḥozai, and claimed half of the family fortune. Mari responded by saying that he did not know the individual who claimed to be his brother. When the case was brought before Rav Huna, he supported Mari’s claim – quoting the passage in Bereishit 42:8, where Yosef recognized his brothers, but they did not recognize him, which showed that Mari may truly be unable to recognize his brother. Rav Huna ruled that the brother must bring witnesses to testify that he was, in fact, Mari’s brother. When the brother claimed that his witnesses were unwilling to come forward, since they were afraid of Mari bar Isak, Rav Huna ruled that Mari must produce witnesses that the man was not his brother. In response to Mari’s question, “dina hakhi?! – Is this really the law?!” Rav Huna explained that this was his ruling for any powerful individual whose implied threats kept people from testifying. In the end, the witnesses did come forward and testified that the man was Mari’s brother.
The Rashba and others argue that Rav Huna’s ruling could not have required Mari bar Isak to produce witnesses that could testify that the claimant was not his brother, since that would have imposed an unreasonable requirement on powerful people, rather Rav Huna demanded that Mari bring the witnesses who had previously declined to testify and ensure that they would come and speak the truth.
Bei Ḥozai – which is known today by its Persian name, Khuzestan – was one of the largest provinces of the Persian Empire, ranging from the mountains of Elam to the Persian Gulf. The long distance between this province – which was an important center of agriculture and commerce – and the central Jewish community in Babylon, as well as the poor roads and infrequent caravans, could make the round trip take as long as a full year. Thus we can well understand how someone in ancient times may lose contact with members of his family who lived in another district.