The relative authority of the high rabbinical courts in Eretz Yisrael and Babylon in Talmudic times has its roots in the deathbed blessing which Yaakov gave to his son Yehuda.

A judge who made an honest mistake in rendering a decision in a financial lawsuit is exempt from compensating the victim of his error only if he was certified as a judge by the head of the high court. But while a judge in Eretz Yisrael could receive such certification from the Exilarch in Babylon or the Nassi who headed the Sanhedrin in his own country, a judge in Babylon could be certified only by the Exilarch and not by the Nassi. The reason for this is that the Exilarch in Babylon was granted authority by the Persian rulers of that country to enforce their rulings with a strong hand, including confiscation of property, a power that the Nassi did not enjoy under Roman rule.

The difference between the two was prophesied by Yaakov when he declared: (Bereishet 49:10) "The staff shall not depart from Yehuda nor the legislator from between his feet."

"Staff", say our Sages, refers to the greater power of the Exilarchs in Babylon, and "legislator" applies to the descendants of Hillel who, in the role of Nassi, taught Torah to the public but enjoyed lesser power than their Babylonian counterparts. Both Exilarch and Nassi, however, were from the Tribe of Yehuda for it was designated by the patriarch as the source of royalty.

In his commentary on Torah, Ramban points out that Yaakovs blessing was no guarantee that there would always be rulers from the Tribe of Yehuda, even in the limited form of Exilarch and Nassi. It was only a directive that whenever Jews enjoy power that it be vested in the hands of that tribe. The first Jewish king, Saul, was not from the Tribe of Yehuda because Hashem looked unfavorably upon the request of the people for a king during the lifetime of the Prophet Shmuel who amply filled the role of leader and therefore provided them with a king from another tribe whose reign was short-lived. Those who ruled over the breakaway Kingdom of Yisrael violated Yaakovs directive and were punished for it. Even the Hasmoneans, whom Ramban describes as "supreme saints who were responsible for the perpetuation of Torah and Mitzvot in Israel", were wiped out by Herod as punishment for holding on to the throne and not restoring it to the Tribe of Yehuda.

King David is praised (Shmuel II 8:15) for is administration of "justice and charity for all of his people".

How do we reconcile justice and charity? ask our Sages, for it is obvious that where strict justice is executed there is no room for charity and vice versa. Several approaches are offered, explaining this apparent paradox.

Rabbi Yehosua ben Korcho saw in this passage a support for his position that in dealing with a financial lawsuit it is proper for the judge to attempt reaching a compromise between the litigants. In this way justice was done by David with no one suffering a total loss, an action which can be viewed as charity as well.

The son of Rabbi Yossi Hagalili, who opposed the idea of a judge seeking compromise rather than strict justice, offered an alternative approach. When David judged a case in which the loser was a poor man he reimbursed him from his own money.

Rebbie (Rabbi Yehuda Hanassi) had a problem with this explanation. The passage states that the charity of David was in regard to "all of his people" and not to the poor alone. He therefore suggests that even without reimbursement David was capable of effecting both justice and charity while judging a case according to the strict rules of judgment. Justice was performed in awarding the money involved to its rightful owner and it was an act of charity to the loser who was relieved of the guilt of holding on to money which did not belong to him.

In regard to this last approach Maharsha notes that although this description of Davids administration of justice was no different than that of any judge, the passage calls attention to it as the merit which enabled Davids general, Yoav ben Tzeruya, to lead his army in triumph as Rabbi Abba bar Kahana (Sanhedrin 49a) points out on the basis of this passages concluding words.