Hastings' Dictionary of the Bible (1898)
SAN'HEDRIN, incorrectly but commonly SAN'HEDRIM. " The Sanhedrin was the highest council of the Jews. When it was founded is uncertain. The Jews trace back to the time of Moses, and see its beginning in the elders. Others see the germ in the tribunal established by Jehoshaphat. 2 Chr 19:8-11. c. 107.
We must distinguish between two kinds of Sanhedrin - the provincial, which was composed of twenty-three members in every town of 120, and of three where there was a smaller, population, and the Great Sanhedrin, which numbered seventy-one and was governed by a nasi, or president, and two vice-presidents; besides, there were secretaries and other officers. It met in a room adjoining the temple, and the seats were arranged in the form of a semicircle. d. 425. It had greatly changed its character before it ended.
It appears, from the statements in the Talmud, that Herod put all the Great Sanhedrin to death except one. But, although this be false, the complexion of the body was altered for the worse. " But in its glory it was the supreme privy council of the Jews - not only their court of final appeal and last resort, but also an executive and legislative assembly, shaping the general polity of the nation. Its power in matters civil and religious was practically unlimited.
It decided all cases brought upon appeal from the lower courts; it had authority over kings and high priests; in it was vested the trial of heresy, idolatry, false prophets; and it alone had power to pronounce the sentence of death. When the Jews came under the Roman government the range of its jurisdiction was decreased. The death power, according to Talmudic tradition, was taken from it three years before the death of Christ. Owing to its altered character, it declined in influence until its extinction was no loss.
The Sanhedrin consisted of the three classes, the priests, the elders, and the scribes. The confirmation and execution of a capital sentence rested with the Roman procurator. The Gospels truthfully, therefore, relate that, while Christ was condemned by the Sanhedrin for blasphemy, he was accused by the Jews of treason, and thus brought under Roman judgment. Cf. " The stoning of Stephen, Acts 7:57-59, was either tumultuous or else, if ordered by the Sanhedrin, illegal, as Josephus (Ant. XX. d. 62, during the absence of Albinus, the Roman procurator. See Council.