Answer
In the Garden of Eden, when Adam sinned by eating fruit from the Tree of the Knowledge of Good and Evil, that act of disobedience produced a grave, two-fold effect on the rest of humanity. The first effect was original sin and the second was imputed sin.
Adam, as the head of the human race, caused every person after him to be born into a fallen condition or sinful state. This effect of Adam’s sin is known as original sin and is often referred to as inherited sin. All human beings have inherited a sinful nature through Adam’s original act of disobedience (Romans 5:12–14).
In addition to receiving a fallen nature, all people who came after Adam have been credited with the guilt of Adam’s sin (Romans 5:18). That is the meaning of imputed sin. An imputation is an attribution or a crediting of something. Imputed sin is Adam’s guilt attributed to or credited to us. All humans are counted as having sinned in Adam and thus deserving the same punishment for sin as Adam. Imputed sin affects our standing before God (we are guilty, condemned), whereas original sin affects our character (we are morally ruined). Both original and imputed sin make us subject to God’s judgment.
The term impute is used both legally and financially and means “to designate any action, word, or thing as credited to another person’s account.” Biblically, Adam’s sin was imputed to all his descendants, and they are to be dealt with as guilty. It does not mean they are personally guilty of Adam’s sin, only that his sin was credited to their account, and thus every person participates in the guilt and penalty of that original transgression.
The penalty for sin is death. We are subject to spiritual death, or separation from God in this present life, due to imputed sin: “As for you, you were dead in your transgressions and sins, in which you used to live when you followed the ways of this world and of the ruler of the kingdom of the air, the spirit who is now at work in those who are disobedient. All of us also lived among them at one time, gratifying the cravings of our flesh and following its desires and thoughts. Like the rest, we were by nature deserving of wrath” (Ephesians 2:1–3). If we persist in this state of separation from God, the result is the second death, which is eternal (Revelation 20:11–15).
Physical death is also a penalty for imputed sin: “Therefore, just as sin entered the world through one man, and death through sin, and in this way death came to all people, because all sinned” (Romans 5:12). The guilt of Adam’s sin was directly charged or imputed to the whole human family so that all people are now subject to death (Romans 6:23).
The apostle Paul teaches imputed sin in various passages: “The many died by the trespass of the one man,” “One trespass resulted in condemnation for all people,” “Through the disobedience of the one man the many were made sinners” (Romans 5:15, 18, 19), and “In Adam all die” (1 Corinthians 15:22).
The good news regarding original and imputed sin is that God already had a remedy, a sovereign plan of salvation, even before Adam sinned in the Garden.
The remedy for imputed sin is the atoning work of Jesus Christ: “For just as through the disobedience of the one man the many were made sinners, so also through the obedience of the one man the many will be made righteous” (Romans 5:19). The moment a sinner believes in Jesus and accepts His gift of salvation, the righteousness of Christ is credited to his or her account: “For as in Adam all die, so in Christ all will be made alive” (1 Corinthians 15:22). Believers possess imputed righteousness.
As all people are in Adam, so all believers are in Christ. Being in Christ means that His righteousness is now ours. Through Christ’s sacrificial death on the cross, the sin of humanity was imputed to Christ. Jesus took on Himself the penalty for our sin: “He was delivered over to death for our sins and was raised to life for our justification” (Romans 4:25).
Believers are not yet perfected in righteousness. Nonetheless, they are clothed in the imputed righteousness of Christ: “God made him who had no sin to be sin for us, so that in him we might become the righteousness of God” (2 Corinthians 5:21). Jesus answered the demands of justice for our sin and satisfied the requirements of the Law (Romans 3:25–26; Colossians 2:14).
