How could Adam and Eve not know of good and evil until they ate a fruit?

Answer:

What changes between childhood and adulthood? Children do things that are wrong at times, but we understand that they don't fully grasp the concept of personal responsibility when it comes to moral decisions. Things are right or wrong because parents tell them. As a result, we don't hold children to the same level of responsibility as we do adults. An example of this is when God held the Israelite adults responsible for rebellion but not their children. "Moreover, your little ones who you said would become a prey, and your sons, who this day have no knowledge of good or evil, shall enter there, and I will give it to them and they shall possess it" (Deuteronomy 1:39).

But somewhere during adolescence, this all changes. A child thinks nothing of being naked unless an adult tells him to get some clothes on. A teenager yells if someone opens the door while he is getting dressed. This change in attitude appears seemingly overnight. Something changed in the brain's wiring during adolescence that makes an individual aware of moral standards. Again, we see this change in Adam and Eve. Prior to eating the fruit, "And the man and his wife were both naked and were not ashamed" (Genesis 2:25). But after eating the fruit we read, "Then the eyes of both of them were opened, and they knew that they were naked; and they sewed fig leaves together and made themselves loin coverings" (Genesis 3:7).

Adam and Eve did not go through puberty. They were formed as adults, but their thinking in some ways was childlike. However, something about eating the fruit of the Knowledge of Good and Evil caused a change in their knowledge of morality and that change is replicated with each child born since that time.

The phrase "good and evil" relates to making moral choices.

1. A woman from Tekoa approached King David. "Then your maidservant said, 'Please let the word of my lord the king be comforting, for as the angel of God, so is my lord the king to discern good and evil. And may the LORD your God be with you.'" (II Samuel 14:17). She connects the ability to correctly distinguish between good and evil decisions to being like an angel of God.
2. When Solomon prayed for wisdom, he said, "Now, O LORD my God, You have made Your servant king in place of my father David, yet I am but a little child; I do not know how to go out or come in. Your servant is in the midst of Your people which You have chosen, a great people who are too many to be numbered or counted. So give Your servant an understanding heart to judge Your people to discern between good and evil. For who is able to judge this great people of Yours?" (I Kings 3:7-9). Solomon realized that he was too childlike in his thinking. He needed greater maturity and understanding to lead God's people and to make proper moral decisions.
3. "But Barzillai said to the king, 'How long have I yet to live, that I should go up with the king to Jerusalem? I am now eighty years old. Can I distinguish between good and bad? Or can your servant taste what I eat or what I drink? Or can I hear anymore the voice of singing men and women? Why then should your servant be an added burden to my lord the king?'" (II Samuel 19:34-35). People understand that there can come a time in old age when the ability to make sound moral decisions is lost. This is one reason children are to take care of their parents in their old age.
4. In a prophecy about the Messiah, Isaiah speaks of his childhood. "He will eat curds and honey at the time He knows enough to refuse evil and choose good. For before the boy will know enough to refuse evil and choose good, the land whose two kings you dread will be forsaken" (Isaiah 7:15-16). Children don't have sufficient knowledge to know how to refuse a bad moral choice, but eventually, that time comes.
5. "For though by this time you ought to be teachers, you have need again for someone to teach you the elementary principles of the oracles of God, and you have come to need milk and not solid food. For everyone who partakes only of milk is not accustomed to the word of righteousness, for he is an infant. But solid food is for the mature, who because of practice have their senses trained to discern good and evil" (Hebrews 5:12-14). A lack of knowledge makes a person immature in their ability to see the difference between good and evil. The maturity that comes from putting God's teachings into daily practice gives a person the ability to distinguish good and evil.

Adam and Eve were created physically mature, but they lacked the experience to see the difference between good and evil choices. God told them what was right and what wrong, but they had not experienced evil personally. The presence of the tree gave them the opportunity to make a choice between heeding God's command or the suggestion of an animal (who was Satan in disguise). The act of eating from the forbidden tree opened their eyes to the distinction between good and evil, much as God granted Solomon wisdom beyond his age and experience. After eating, God said, "Behold, the man has become like one of Us, knowing good and evil" (Genesis 3:22). Adam could see the difference between good choices and bad choices independently because he experienced evil directly. Sadly mankind still picks the bad choices at times (Romans 3:23). In other words, the knowledge of morality doesn't mean the person makes good choices.