“having a good conscience, that when they defame you as evildoers, those who revile your good conduct in Christ may be ashamed” (1 Peter 3:16).
The following definition can help enhance our understanding of the word “conscience” in the context of 1 Peter 3:16…
Conscience (noun) 1. the internal sense of what is right and wrong that governs somebody’s thoughts and actions, urging him or her to do right rather than wrong.
2. behavior in compliance with what your internal sense of right and wrong tells you is right. (1)
To this, we can add the following definition from the original language of this passage: “the soul as distinguishing between what is morally good and bad, prompting to do the former and shun the latter, commending one, condemning the other.” (2) So, much like an umpire, judge, or referee, our consciences arbitrate the differences between right and wrong.
Another commentator expands upon these definitions in a practical manner…
“Paul uses this term twice in his trials in Acts (cf. Acts 23:1 and 24:16). It refers to his sense that he had not knowingly violated any expected duties toward God (cf. 1 Cor. 4:4). Conscience is a developing understanding of believers’ motives and actions based on 1. a biblical worldview 2. an indwelling Spirit 3. a knowledge of the word of God 4. the personal reception of the gospel. Peter has used this expression three times, 1 Pet. 2:19; 3:16 and 21. This is exactly what religious legalism could not provide, but the gospel can.” (3)
This idea also builds upon a foundation that the Apostle Peter established in an earlier portion of this letter: “having your conduct honorable among the Gentiles, that when they speak against you as evildoers, they may, by your good works which they observe, glorify God in the day of visitation” (1 Peter 2:12). The correlation is this: we can maintain a clear conscience if the suffering we encounter stems from our allegiance to Christ rather than misconduct on our part.
Finally, we should note that our consciences are not infallible arbiters of moral behavior. For instance, it is possible for two people to act in good conscience while pursuing different courses of action. As Paul the Apostle said to the Corinthian church, “My conscience is clear, but that does not make me innocent. It is the Lord who judges me” (1 Corinthians 4:4 NIV). Nevertheless, our consciences can serve as excellent guides whenever they are led and informed by God’s Word.
(1) “Conscience” Encarta® World English Dictionary © 1999 Microsoft Corporation. p.403
(2) G4893 syneidesis https://www.blueletterbible.org/lexicon/g4893/kjv/tr/0-1/
(3) Dr. Bob Utley. Free Bible Commentary – 1 Peter 3, Copyright © 2014 Bible Lessons International http://www.freebiblecommentary.org/new_testament_studies/VOL02/VOL02B_03.html
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