SYNEDRIUM (avvtdpiov) , a Greek word which means " assembly " and is especially used of judicial or representative assemblies, is the name by which (or by its Hebrew transcription , j-nnjo, sanhedrin, sanhedrim) that Jewish body is known which in its origin was the municipal council of Jerusalem, but acquired extended functions and no small authority and influence over the Jews at large (see xiii. 424 seq.). In the Mishnah it is called " the sanhedrin," " the great sanhedrin," " the sanhedrin of seventy-one [members] " and " the great court of justice " (beth din haggdddl). The oldest testimony to the existence and constitution of the synedrium of Jerusalem is probably to be found in 2 Chron. xix. 8; for the priests, Levites and hereditary heads of houses there spoken of as sitting at Jerusalem as a court of appeal from the local judicatories does not correspond with anything mentioned in the old history, and it is the practice of the chronicler to refer the institutions of his own time to an origin in ancient Israel. And just such an aristocratic council is what seems to be meant by the gerousia or senate of " elders " repeatedly mentioned in the history of the Jews, both under the Greeks from the time of Antiochus the Great (Jos. Ant. xii. 3, 3) and under the Hasmonean high priests and princes. The high priest as the head of the state was doubtless also the head of the senate, which, according to Eastern usage, exercised both judicial and administrative or political functions (cf. i Mace. xii. 6, xiv. 20). The exact measure of its authority must have varied from time to time at first with the measure of autonomy left to the nation by its foreign lords and afterwards with the more or less autocratic power claimed by the native sovereigns.
The original aristocratic constitution of the senate began to be modified under the later Hasmoneans by the inevitable introduction of representatives of the rising party of the Pharisees, and this new element gained strength under Herod the Great, the bitter enemy of the priestly aristocracy. Finally under the Roman procurators the synedrium was left under the presidency of the chief priest as the highest native tribunal, though without the power of life and death (John xviii. 31). The aristocratic and Sadducean element now again preponderated, as appears from Josephus and from the New Testament, in which " chief priests " and " rulers " are synonymous expressions. But with these there sat also " scribes " or trained legal doctors of the Pharisees and other notables, who are simply called " elders " (Mark xv. i). The Jewish tradition which regards the synedrium as entirely composed of rabbins sitting under the presidency and vice-presidency of a pair of chief doctors, the nasl and db beth din, is inconsistent with the evidence of Josephus and the New Testament. It is generally held that it was after the fall of the state that a merely rabbinical beth din sat at Jabneh and afterwards at Tiberias, and gave legal responses to those who chose to admit a judicature not recognized by the civil power. Dr A. Biichler has sought to reconcile the various accounts by the theory that there were two great tribunals in Jerusalem, one wielding religious, the other civil authority (Das Synedrion in Jerusalem, Vienna, 1^02).
The council chamber (fiov\rj) where the synedrium usually sat was between the Xystus and the Temple, probably on the Templehill, the Mishnah states that the meetings were held within the inner court. The meeting in the palace of the high priest which condemned Jesus was exceptional. The proceedings also on this occasion were highly irregular, if measured by the rules of procedure which, according to Jewish tradition, were laid down to secure order and a fair trial for the accused.
Of the older literature of the subject it is enough to cite Selden, De synedriis. The most important critical discussion is that of Kuenen in the Verslagen, etc., of the Amsterdam Academy (1866), p. 131 seq. A good summary is given by Schiirer, Geschichte des judischen Volkes, 4th ed., 23. Cf. also G. A. Smith, Jerusalem (1907), vol. i. ch. 9.
Note - this article incorporates content from Encyclopaedia Britannica, Eleventh Edition, (1910-1911)