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Hastings' Dictionary of the New Testament [1]

The judge invariably sat on a special ‘seat’ or throne. Thus Jerusalem and the smaller cities alike had their ‘thrones for judgement’ ( Judges 4:5,  1 Kings 7:7,  Psalms 122:5, etc.). In Rome magistrate and jury were seated together on the raised tribunal , or ‘bench,’ the magistrate oh his sella curulis , or ‘chariot seat,’ specially associated with the Roman imperium . The custom extended also to the Provinces. In the NT κριτήρια (‘tribunals’) is used of law-courts generally (in  1 Corinthians 6:2;  1 Corinthians 6:4 and  James 2:6), while βῆμα, lit.[Note: literally, literature.]‘step,’ ‘seat’ (for parties in a law-suit), is applied to the ‘judgment-seat’ not only of the Emperor ( Acts 25:10), but also of the governors Pilate ( Matthew 27:19,  John 19:13), Gallio ( Acts 18:12;  Acts 18:16 f.) and Festus ( Acts 25:6;  Acts 25:17), and even metaphorically of God ( Romans 14:10) and Christ ( 2 Corinthians 5:10). See, further, Trial-at-Law.

A. R. Gordon.

Hastings' Dictionary of the Bible [2]

JUDGMENT-SEAT. The usual word employed for this in the NT is bçma (  Matthew 27:19 ,   John 19:13 ,   Acts 18:12;   Acts 18:16 f.,   Acts 25:6;   Acts 25:10;   Acts 25:17 ,   Romans 14:10 ,   2 Corinthians 5:10 ), properly a ‘tribune.’ In the NT the word is used of the official seat (tribunal) of the Roman judge. The word kritçrion used in   James 2:5 occurs also in   1 Corinthians 6:2;   1 Corinthians 6:4 , where it is translated in RVm [Note: Revised Version margin.] by ‘tribunal.’ See, further, art. Gabbatha.