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conscience, the English translation of a word that, in classical Greek, referred to knowledge, especially the knowledge derived from reflection on one’s past deeds. The appraisal of these deeds determined whether the conscience was ‘good’ or ‘bad.’ The focus of OT faith is primarily on Israel’s relation to God, and the Greek idea of conscience as self-reflection finds little place. Something similar to the concern for a ‘clear conscience’ before God is expressed, however, in the OT desire for a ‘clean heart’ (e.g., Ps. 51:10), and a usage similar to that in the Hellenistic world is found in the Wisdom of Solomon 17:11.

In the NT, which appears to be influenced by Hellenistic usage, the term occurs some thirty times, primarily in Paul’s Letters (Romans and 1 and 2 Corinthians) and in other writings traditionally associated with Paul (the pastoral Letters), although it also occurs twice in Acts (23:1; 24:16, both times on the lips of Paul), five times in Hebrews (9:9, 14; 10:2, 22; 13:18), and three times in 1 Peter (2:19; 3:16, 21). In a few instances, the meaning apparently is something like ‘consciousness’ or ‘awareness’ (Heb. 10:2; 1 Pet. 2:19, rsv: ‘mindful’). Elsewhere, the writers can speak of a ‘good’ or ‘bad’ conscience (Acts 23:1; 24:16; 1 Tim. 1:5, 19; 3:9; 4:2; 2 Tim. 1:3; Titus 1:15; Heb. 10:22; 13:18; 1 Pet. 3:16, 21) or of ‘perfecting’ or ‘purifying’ the conscience (Heb. 9:9, 14).

Paul’s use of the term is somewhat more difficult to characterize. In Rom. 2:15; 9:1 and 2 Cor. 1:12, he apparently uses it in the sense of one’s knowledge or awareness of the nature of one’s own thoughts, motives, and actions. In 2 Cor. 4:2 and 5:11, it appears to refer to one’s judgments regarding the motives and actions of another. The exact meaning in Rom. 13:5 is unclear. Paul’s understanding of the role of conscience is most fully expressed in his correspondence with the Corinthians concerning eating food offered to idols (1 Cor. 8-10). Some Corinthians apparently decided to let their conscience be their guide in this matter. Paul responds that conscience alone is an inadequate guide for Christian ethics. In an extremely sensitive or weak Christian, conscience may become too critical and oppressive. The stronger Christian, on the other hand, may be inconsiderate of the scruples of the weaker Christian. Paul does not think additional knowledge per se will be a sufficient guide for behavior in such a situation; rather, he admonishes that conscience follow the love ethic.

BibleTexts.com note: The Greek word translated as "conscience" is suneidesis, which is Strong's number 4893.