The book of Genesis does not give an ultimate explanation of the origin of evil, for evil is at its heart not explicable or intelligible, just as darkness is by its nature not visible. It stems not from a positive presence but from an absence, not a reason but a form of unreason: a failure, a lack, as darkness is the absence that comes when light fails. Still, the darkness can have a shape determined by the light, as when we see a well-defined shadow. So we can describe the shape of the evil and failure in Genesis 3, which becomes visible when we see the good things that are missing.
Most important is the absence of truth. This comes in five forms: the man is silent, the woman is mistaken, and the serpent lies—and then, as a result, the woman is deceived and the man sins in unbelief, not heeding the truth of God’s word.
Adam stands silently by while the serpent lies. He has heard firsthand the commandment of God that the serpent teaches his wife to disobey, and he says nothing about it. He does not remind her, does not teach her, does not warn her. This may be the continuation of a pattern, for it appears from the woman’s mistakes that he has not done a good job teaching her what God has said.
The woman in fact makes two mistakes about what God said. Both mistakes are in themselves innocent. First, she adds to God’s word, reporting the prohibition, “you shall not eat it” and adding the gloss, “neither shall you touch it” as if this were God’s own speech (Gen. 3:3). Though God did not say this, believing it will not lead to disobedience. In fact it would have the effect of “fencing the Torah,” putting a kind of hedge around what is forbidden so as to make the commandment impossible to disobey. So far, no harm done.
Second, she appears to be a bit vague about which tree is forbidden. She says it is “the tree in the midst of the garden” (3:3), which is the description given earlier in Genesis to the tree of life (2:9). Perhaps she is not so far wrong; the original phrasing leaves open the possibility that the tree of knowledge is also in the midst of the garden. But there is the danger here that she might unwittingly violate the commandment through her ignorance of exactly what God said.
Where did these mistakes come from? Has she failed to understand what Adam told her? Or has he failed to teach her clearly? Here we have yet another gap in the narrative, a piece of narrative artistry requiring us to think about what has happened. I think the point is that the obedience of the man and the woman requires them both to do their part: he telling her about the word of God which he heard firsthand before she was created , she listening as well as strengthening him in the task of obedience, as a helper fit for him, a kind of ally to strengthen him (which is the biblical meaning of a “helper”). Instead, she listens to the serpent rather than to her husband, and strengthens him only for disobedience, as Jezebel does to Ahab .
Thus instead of moving from hearing God’s word to obedience and then to wisdom, which is a tree of life (Prov. 3:18) , the man and his wife move together from falsehood to disobedience and then to death. At the heart of their evil is unbelief. It is a failure the two of them share. Failing to speak, failing to hear, between them they miss the truth of God’s word.
It is like a team that drops the ball: bad pass, bad catch—both. But the team’s failure does not eliminate individual responsibilities. The woman is deceived, the man is not (see 1 Tim. 2:14). He knows better. He would rather get the fruit he wants than obey the voice of God. When he abets the lie by his silence, he is actively suppressing the truth in unbelief. That is why, following Paul, we call this first sin Adam’s. He is “the one man” through whom “sin came into the world . . . and death through sin” (Rom. 5:12).