It is commonplace to hear the statement, "people are basically good." Though it is admitted that no one is perfect, human wickedness is minimized. Yet if people are basically good, why is sin so universal?
It is often suggested that everybody sins because society has such a negative influence upon us. The problem is seen with our environment, not with our nature. This explanation for the universality of sin begs the question, how did society become corrupt in the first place? If people are born good or innocent, we would expect at least a percentage of them to remain good and sinless. We should be able to find societies that are not corrupt, where the environment has been conditioned by sinlessness rather than sinfulness. Yet the most dedicated-to-righteousness communes we can find still have provisions for dealing with the guilt of sin.
Since the fruit is universally corrupt we look for the root of the problem in the tree. Jesus indicated that a good tree does not produce corrupt fruit. The Bible clearly teaches that our original parents, Adam and Eve, fell in sin. Subsequently, every human being has been born with a sinful and corrupt nature. If the Bible didn't explicitly teach this, we would have to deduce it rationally from the bare fact of the universality of sin.
Yet the Fall is not simply a question of rational deduction. It is a point of divine revelation. It refers to what we call original sin. Original sin does not refer primarily to the first or original sin committed by Adam and Eve. Original sin refers to the result of the first sin—the corruption of the human race. Original sin refers to the fallen condition in which we are born.
That the Fall occurred is clear in Scripture. The Fall was devastating. How it came to pass is open to dispute even among Reformed thinkers. The Westminster Confession explains the event simply, much in the manner that Scripture explains it:
Our first parents, being seduced by the subtlety and temptation of Satan, sinned, in eating the forbidden fruit. This their sin, God was pleased, according to His wise and holy counsel, to permit, having purposed to order it to His own glory.
Thus, the Fall occurred. The results, however, reached far beyond Adam and Eve. They not only touched all mankind, but decimated all mankind. We are sinners in Adam. We cannot ask, "When does the individual become a sinner?" For the truth is that human beings come into existence in a state of sinfulness. They are seen by God as sinful because of their solidarity with Adam.
The Westminster Confession again elegantly expresses the results of the Fall, particularly as it relates to human beings:
By this sin they fell from their original righteousness and communion with God, and so became dead in sin, and wholly defiled in all the parts and faculties of soul and body. They being the root of all mankind, the guilt of this sin was imputed, and the same death in sin, and corrupted nature, conveyed to all their posterity descending from them by ordinary generation. From this original corruption, whereby we are utterly indisposed, disabled, and made opposite to all good, and wholly inclined to all evil, do proceed all actual transgressions.
That last phrase is crucial. We are sinners not because we sin. Rather, we sin because we are sinners. Thus David laments, "Surely I was sinful at birth, sinful from the time my mother conceived me" (Psalm 51:5, NIV).