The fallen world in which we live rests on the foundations of a creation that was good. Yet, it had scarcely been created before sin crept into it. The origin of sin is a mystery; it is not from God, and at the same time it is not excluded from his counsel. God decided to take humanity on the perilous path of covenantal freedom rather than elevating it by a single act of power over the possibility of sin and death.
Genesis 2:9 speaks of two trees, the tree of life and the tree of the knowledge of good and evil. Both are integral to the Genesis narrative, and attempts to discount one or the other destroy narrative meaning. Similarly, efforts to explain the meaning of either of the trees in terms of progress and development (tree of life as awakening of sexuality) ignore the plain reading of prohibition and punishment associated with eating the trees’ fruit. No, the story is a unity, and it is about the fall of humanity and the origin of sin. Genesis 3 is not a step of human progress but a fall.
This fall, however, is not simply human effort to achieve cultural power as a means of becoming independent from God. The Bible does not portray human cultural formation as an evil in itself so that rural simplicity is preferable to a world-dominating culture. The point of the “fall” narrative in Genesis is to point to the human desire for autonomy from God. To “know good and evil” is to become the determiner of good and evil; it is to decide for oneself what is right and wrong and not submit to any external law. In short, to seek the knowledge of good and evil is to desire emancipation from God; it is to want to be “like God.”
The entry into sin comes by way of the serpent’s lie. The serpent’s speaking has often been mistakenly considered an allegory for lust, sexual desire, or errant reason. The various mythical interpretations and even attempts to explain the narrative in terms of animal capacity for speech before the fall all fail to meet the intent of the passage and the teaching of Scripture as a whole. The only appropriate explanation is to recognize, with ancient exegesis, the entrance of a spiritual superterrestrial power. The rest of the Bible, however, is relatively silent about this, though its entire narrative rests on this spiritual conflict between the two kingdoms. Sin did not start on earth but in heaven with a revolt of spiritual beings. In the case of humanity, the temptation by Satan resulted in the fall. Scripture looks for the origin of sin solely in the will of rational creatures.