When God made man, he put him in the garden of Eden and told him to work it and keep it. He commanded him, "You may eat of any tree in the garden except for the tree of knowledge of good and evil. The day that you eat of it, you will surely die." It is important to note that the you in this passage is singular, given to Adam alone.
Then God said, "It is not good for man to be alone. I will make him a helper fit for him." So God put Adam to sleep and made from his side a woman. When he awoke, Adam was excited and said, "Bone from my bone, and flesh from my flesh; she shall be called woman [Hebrew isha] because she was taken out of man [ish]." And Adam named her Eve.
One day the Snake, identified in Revelation 12:9 as Satan or the Devil, said to the woman, "Did God really say, 'You [plural] shall not eat of any tree in the garden'?" The woman replied, "We may eat the fruit of any tree in the garden, but God said, 'You [plural] shall not eat from the fruit of the tree in the middle of the garden nor shall you touch it, so that you [plural] will not die." Adam must have told Eve about this, for the command has changed from singular to plural, and rightly so, for Eve was taken out of Adam. But for Eve's benefit, Adam had added to the command, "nor shall you touch it." He had in effect "built a fence around the command." If she didn't touch it, she couldn't eat it. Now people may personally "build a fence" around something to avoid temptation. Perhaps there are certain kinds of movies that a person refuses to see lest they are tempted. The problem occurs when people build fences for others. When Eve touched the fruit and nothing happened, she was emboldened to go ahead and eat the fruit. The same thing can happen to people today. When they break the "fence" command, they are emboldened to break God's command.
The Snake then told Eve a lie, "You [plural] will not surely die. God knows that when you [plural] eat of it, your [plural] eyes will be opened and you [plural] will be like God, knowing good and evil." Jesus says in John 8:44 that the devil is a liar and the father of lies. I sometimes wonder what it means to know good and evil in this context. They already knew it was good to keep and till the garden and that it was evil to eat the fruit of the tree in the middle of the garden. It seems that "knowing good and evil" has to do with deciding for themselves what is good and what is evil. When God made people, He saw that it was very good (Gen. 1:31). But when they sinned, they decided that it was not good to be naked the way God had made them. Now God ratified their decision to wear clothes, making better ones for them (Gen. 3:21). But the point is that they decided for themselves what was good and what was evil. Unfortunately, we often do the same thing instead of recognizing what God says is good and evil.
John says in I John 2:16 that there are three kinds of sin in this world: the desires of the flesh, the desires of the eyes, and the pride in what we have in life. It is worth noting that Eve was tempted in all three of these ways. She saw that the tree was good for food (desire of the flesh), that it was pleasing to the eyes (desire of the eyes), and that it would make one wise (pride of life). Jesus was tempted by Satan in the wilderness in the same three ways. He was asked to turn stones to bread (desire of the flesh), worship Satan for all the world he could see (desire of the eyes), and jump off the temple to prove he was God's Son (pride of life). But while Eve gave into the temptation and sinned, Jesus overcame the temptation by quoting scripture in each instance. Sometimes I hear that one should pray when tempted. It is never wrong to pray, but praying keeps the focus on the temptation. Jesus' example replaces the temptation with the word of God.
After Eve ate the fruit, she gave some to her husband who was with her and he also ate. I have sometimes heard people blame Adam for letting Eve be tempted and go ahead and eat since the text says that he was "with her." Some go so far as to say that Adam heard the lie and faced the same temptation. But God blamed Adam because he listened to his wife (Gen. 3:17), not to the Snake. While the word "with" can be used to mean with Eve at the temptation, it can also be used to mean with her in the garden. Jacob told Laban that he was "with" him (same word in Hebrew) for twenty years while he took care of his flocks in the field.
After Adam and Eve had eaten the fruit, their eyes were "opened" and they knew that they were naked. To solve this problem, they made loincloths for themselves from fig leaves. This brings us to the first problem with sin: sin brings shame. They were ashamed of the way God had made them. When they heard God walking in the garden in the cool of the day, they hid themselves among the trees.
God called to Adam, "Where are you [singular]?" Adam replied, "When I heard the sound of You walking in the garden, I was afraid since I was naked, so I hid myself." This is the second problem with sin: sin brings fear, fear of being seen by God. God asked Adam, "Who told you [singular] that you [singular] were naked? Have you [singular] eaten of the tree from which I commanded you [singular] not to eat?" Note that God confronted Adam because it was to Adam alone that God had given the command. This is why Paul can write that sin came into the world because of one man and that one man brought in the reign of death (Rom. 5:12, 17). We sometimes like to place the blame on Eve, but God put the blame on Adam.
When Adam was blamed, he began to make excuses and put the blame on Eve and indirectly on God: "The woman whom You gave to be with me, she gave me the fruit from the tree and I ate." So God asked the woman, "What is this that you [singular] have done?" The woman also began to blame someone else: "The snake deceived me and I ate." This is why Paul says that it was the woman who was deceived (I Tim. 2:14).
So God cursed the snake to crawl on its belly. He also gave a hint of Christ's death and victory over Satan. He told the snake that the woman's Offspring would bruise his head, but the snake would bruise the Offspring's heel. This is a veiled reference to the nail in Christ's heel on the cross.
Then God placed a curse on the woman. She would suffer more pain in childbirth and her relationship to the man would change. God told her, "Your desire shall be for your husband, and he shall rule over you." It is possible to misread this as saying that the woman would desire her husband, but the meaning is that she would desire to control him. It is parallel to what God told Cain, "Sin's desire is for you, but you must rule over it" (Gen. 4:7). Sin desired to control Cain because of his anger and he failed to rule over it and ended up killing his brother.
Finally God placed a curse on the man. He cursed the earth to bring forth thorns and thistles, and consequently man would suffer pain in working the land by the sweat of his brow. Man would also die, returning to dust, just as God said he would. Oh, it wasn't on that very day, but on that day he was now "a dead man walking." His coming death was sure. This is the third result of sin: sin brings consequences. Even when there is forgiveness, there are still consequences to pay.
I have sometimes heard that when Adam sinned he was spiritually dead (Eph. 2:1) and separated from God (Is. 59:2). While in some sense this is true, it seems to underestimate God's mercy and forgiveness. God still seeks Adam in the garden and confronts both Adam and Eve. God's forgiveness is shown in the garments of skin he made for them. Eve said that God helped her to give birth (Gen. 4:1). It was even a blessing when he ejected them from the garden. The tree of life was there and if they ate of it, they would live forever in sin. But God in His mercy had a better plan for them. That plan involved the death and resurrection of Jesus to take away sin. And God has that same plan for all of us; Jesus died and rose for us all, for, like Adam, we have all broken God's commandments and need forgiveness from sin, that forgiveness that is found in Jesus.