And right from the start the first man possessed a God-given conscience; it was not something that simply developed as society grew. This can be seen in the account of Adam’s actions and attitude after he broke God’s command concerning the tree of the knowledge of good and bad. (Gen. 2:17) The record says that Adam and Eve then “went into hiding from the face of Jehovah God in between the trees.” And when Jehovah spoke, Adam did not quickly respond. Why not? Because he sensed his guilt; it was as if there were a voice within him that was condemning him, accusing him, testifying that he had sinned.​—Gen. 3:7-10.

The Egyptians, along with people earth wide, realized that adultery was a grave moral offense. Their oldest religious texts associated the Last Judgment with the weighing of the “heart.” And over what was one judged? The ancient Egyptian “Book of the Dead” depicts the deceased as declaring his innocence, saying, ‘I have not robbed. I have not killed men. I have not lied. I have not defiled any man’s wife.’ So, it must be that conscience led them to sense the wrongness of adultery. Bringing conscience into the picture, historian Josephus later wrote of Joseph’s urging Potiphar’s wife to shun a lust that would bring remorse and suffering, but to be faithful to her husband and enjoy “a good conscience.”

11. How do both Biblical and non-Biblical sources illustrate a functioning conscience?

¹¹ Additionally, we find both Biblical and non-Biblical descriptions that illustrate a functioning conscience. On one occasion King David of Israel had a census of the nation taken. The Bible describes David’s reaction when he realized that he had sinned. Showing the operation of conscience, the Bible says that “David’s heart began to beat him.” (2 Sam. 24:1-10) A similar effect of a smitten conscience is mentioned in an ancient cuneiform tablet that gives the prayer of a Babylonian who had sinned. He implored his god to listen “on account of his breast, which complains like a resounding flute.”

12. (a) So, what can correctly be concluded about the faculty of conscience, as pointed out by the apostle Paul? (b) Is conscience manifested by all people?

¹² All of this shows that we have a conscience because of inheriting intelligence and a moral sense from Adam. Thus, even nations that knew nothing of the Mosaic law, given by God, forbade things such as stealing, lying, incest, murder and adultery. Yes, though they “do not have law,” they “do by nature the things of the law.” The apostle Paul highlighted the basis for their moral standards, saying, “their conscience [Greek, syneiʹdesis] is bearing witness with them and, between their own thoughts, they are being accused or even excused.” (Rom. 2:14, 15)

Likely the most commonly-thought-of operation of conscience is that of looking back and judging one’s past moral performance. We noted this function in the case of Adam’s sin and the experience of David after he had acted improperly. Their consciences smote them. Have you not felt your conscience operating in this way? This inner voice of conscience afflicting those who have done wrong can be so insistent that they take drastic action to clear their conscience or they may be pained by their conscience for years.

15. This can help you in what important way?

¹⁵ A far more important effect, though, of this operation of conscience is that it may move one to godly repentance. David wrote: “When I kept silent my bones wore out through my groaning all day long. My sin I finally confessed to you, and my error I did not cover. I said: ‘I shall make confession over my transgressions to Jehovah.’ And you yourself pardoned the error of my sins.” (Ps. 32:3, 5) Thus, your functioning conscience can bring you back to God, aiding you to recognize the need to have his forgiveness and to follow his ways in the future.​—Ps. 51:1-4, 9, 13-15.