Easton's Bible Dictionary (1897)
More correctly Sanhedrin (Gr. ) is frequently used in the New Testament (Matt. 5:22; 26:59; Mark 15:1, etc.) to denote the supreme judicial and administrative council of the Jews, which, it is said, was first instituted by Moses, and was composed of seventy men (Num. 11:16, 17). But that seems to have been only a temporary arrangement which Moses made. This council is with greater probability supposed to have originated among the Jews when they were under the domination of the Syrian kings in the time of the Maccabees. The name is first employed by the Jewish historian Josephus.
This “council” is referred to simply as the “chief priests and elders of the people” (Matt. 26:3, 47, 57, 59; 27:1, 3, 12, 20, etc.), before whom Christ was tried on the charge of claiming to be the Messiah. Peter and John were also brought before it for promulgating heresy (Acts. 4:1-23; 5:17-41); as was also Stephen on a charge of blasphemy (6:12-15), and Paul for violating a temple by-law (22:30; 23:1-10). The Sanhedrin is said to have consisted of seventy-one members, the high priest being president.
They were of three classes (1) the chief priests, or heads of the twenty-four priestly courses (1 Chr. 24), (2) the scribes, and (3) the elders. As the highest court of judicature, “in all causes and over all persons, ecclesiastical and civil, supreme,” its decrees were binding, not only on the Jews in Palestine, but on all Jews wherever scattered abroad. Its jurisdiction was greatly curtailed by Herod, and afterwards by the Romans.
Its usual place of meeting was within the precincts of the temple, in the hall “Gazith,” but it sometimes met also in the house of the high priest (Matt. 26:3), who was assisted by two vice-presidents.