The term original sin refers to Adam’s sin of disobedience in eating from the tree of knowledge of good and evil and its effects upon the rest of the human race. Original sin can be defined as “the moral corruption we possess as a consequence of Adam’s sin, resulting in a sinful disposition manifesting itself in habitually sinful behavior.” The doctrine of original sin focuses particularly on its effect on our internal nature and our standing before God. There are three main views that deal with that effect:
Pelagianism: This view says that Adam’s sin had no effect upon the souls of his descendants other than that he provided a sinful example. Adam’s example has influenced those who followed him to also sin. But, according to this view, man has the ability to stop sinning if he simply chooses to. Pelagianism runs contrary to a number of passages that indicate man is hopelessly enslaved by his sins (apart from God’s intervention) and that his good works are “dead” or worthless in meriting God’s favor (Ephesians 2:1–2; Matthew 15:18–19; Romans 7:23; Hebrews 6:1; 9:14).
Arminianism: Arminians believe Adam’s original sin has resulted in the rest of mankind inheriting a corrupt, sinful nature, which causes us to sin in the same way that a cat’s nature causes it to meow—it comes naturally. According to this view, man cannot stop sinning on his own; God’s supernatural, enabling grace, called prevenient grace, in conjunction with the gospel, allows that person to choose to exercise faith in Christ. The teaching of prevenient grace is not explicitly found in Scripture.
Calvinism: The Calvinistic doctrine of original sin states that Adam’s sin has resulted not only in our having a sin nature, but also in our incurring guilt before God for which we deserve punishment. Being conceived with original sin upon us (Psalm 51:5) results in our inheriting a sin nature so wicked that Jeremiah 17:9 describes the human heart as “deceitful above all things and beyond cure.” Not only was Adam found guilty because he sinned, but his sin was imputed to us, making us guilty and deserving of his punishment (death) as well (Romans 5:12, 19). There are two views as to why Adam’s sin should be imputed to us. The first view states that the human race was within Adam in seed form; thus, when Adam sinned, we sinned in him. This is similar to the biblical teaching that Levi (a descendant of Abraham) paid tithes to Melchizedek in Abraham (Genesis 14:20; Hebrews 7:4–9), even though Levi was not born until hundreds of years later. The other main view is that Adam served as our representative, and so, when he sinned, we were found guilty as well.
Both the Arminian and Calvinistic views teach original sin and see individuals as unable to overcome sin apart from the power of the Holy Spirit. Most all Calvinists also teach imputed sin; some Arminians deny imputation of sin, and others believe that Christ’s death has negated the effects of imputation.
The fact of original sin means that we cannot please God on our own. No matter how many “good deeds” we do, we still commit sin, and we still have the problem of a corrupt nature within. We must have Christ; we must be born again (John 3:3). God deals with the effects of original sin in our hearts through the process of sanctification. As John Piper puts it, “The problem of our moral defilement and habitual sinning is solved by his purifying us by the work of Spirit” (“Adam, Christ, and Justification: Part IV,” preached 8/20/2000).