XXa-kuz-er: This word, not found in the Old Testament, is the rendering of two Greek words: (1) kategoros, that is, a prosecutor, or plaintiff in a lawsuit, or one who speaks in a derogatory way of another (Acts 23:30,35; 25:16,18; Rev 12:10); (2) diabolos, meaning adversary or enemy. This word is rendered "accuser" in the King James Version and "slanderer" in the Revised Version (British and American) and the American Standard Revised Version (2 Tim 3:3; Titus 2:3). According to the rabbinic teaching Satan, or the devil, was regarded as hostile to God and man, and that it was a part of his work to accuse the latter of disloyalty and sin before the tribunal of the former (see Job 1:6 ff; Zec 3:1 f; Rev 12:10).
W. W. Davies