Knowledge of Good and Evil

By Mary Jane Chaignot

Categories: Old Testament


We read in Genesis 2:9 that God made a tree of the knowledge of good and evil. What kind of a tree is this – and what is "the knowledge of good and evil?"


To begin with, this is the first mention of evil, and it is paired with good. And from this tree comes the knowledge of good and evil. What does this all mean? Scholars generally break down the meaning of good or evil in this context into three main possibilities, and promptly argue against each of them! The first is that the fruit of this tree is the beginning of sexual knowledge. That theory is advanced because after eating from the forbidden tree, Adam and Eve knew they were naked and hid themselves. Prior to this time, they presumably were walking around naked and had no sense of shame. The problem with this is that woman had not yet been created when the tree was mentioned. And back in Genesis 1:27, God himself created them male and female and later made a decree about marriage. It's hard to see why they should be forbidden to eat of this tree on that basis. Most damaging, however, is the line to come, in 3:22. This is after they had eaten from the tree and God said, "Now they have become like one of us." If eating from the tree had to do with sexuality, then God would have had to be sexual from the beginning. Not too many would want to argue this position.

Another option is that this tree encompasses all knowledge, that good and evil is a merism. This word simply means everything, totality, all that there is. The problem here, of course, is that man does not seem to be omniscient after eating from the tree. The only new thing he seemed to know is that he was naked. Many things seemed beyond his ability to understand and continue to be beyond his ability to understand. So, omniscience is a weak argument.

The third option is that this was the beginning of man's moral development, that now he had the capacity to reason and to make moral decisions. One might say that he was forbidden to eat from this tree because whenever man starts making his own decisions, he gets himself into trouble. The problem, of course, is that if this was the beginning of his moral development, how did he know it was wrong before he ate the fruit?

The lack of a consensus in the matter impels us to look to the other uses of the phrase "good and evil" in the Old Testament to get a clearer understanding of its meaning. But those passages are not terribly consistent in their uses either. It can mean moral awareness, but it can also mean knowing the difference between what is pleasant or unpleasant.

Generally, however, it seems to be a quality that adults possess, but that children do not. Deuteronomy 1:39 states, "Your little ones, who you thought would become spoils of war, your children who do not yet know good from bad – they will enter the land." When Solomon had been made king, God asked him in a dream what he would have. Solomon replied, "I am a mere child, unskilled in leadership…Give to your servant therefore a heart with skill to listen, so that he may govern your people justly and distinguish good and bad" (I Kings 3:7-9, NEB). Even though he was grown up, he made his request from the standpoint of a child, unskilled in leadership. Lastly, when King David was returning to Jerusalem after a successful military campaign, he met his old political ally, Barzilla. He invited him to return with him to Jerusalem to live out his final days at the palace. Barzilla, at the ripe old age of 80, said, "Can I tell the difference between what is good and what is not?...." He declined King David's offer, not wanting to be a burden on the throne (II Sam. 19:35). However, in II Sam 14:17, the woman of Tekoa praised David, "For my Lord the king is like an angel of God in discerning good and evil. May the Lord your God be with you."

The common thread among these examples seems to be one of maturity. The first two had not yet reached that point, whereas Barzilla had gone past it. King David had it just right. While scholars find these ideas helpful, they have yet to come to a definitive consensus about the meaning of the tree and the phrase "good and evil."

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