JOEL - This has always been a hard thing for people to understand; myself included. The commands He gave Adam and Eve seem so contradictory. He tells them not to eat the fruit, when it was vital for the success of His entire plan that they do eat it. He tells them to multiply and replenish the earth, when, in their state of innocence, they probably would not do that unless they did partake of the fruit. So why would God give a commandment that He wanted Adam to break?
First of all we need to understand that at the moment Adam and Eve were created, they were still immortal beings who were able to converse with God and learn from Him about the premortal life and plan of salvation while in the garden. There was no veil between them and God before the fall. God walked and talked with Adam and Eve and most certainly made them aware of His plan. Even though in their inocent state they did not comprehend good and evil, they did have a knowledge of God's plan of salvation.
The commands God gave Adam and Eve were not necessarily contradictory; He was simply giving them the opportunity to choose for themselves; an eternal principle that had to be followed even in this case. God was simply telling Adam that if he wanted to stay in the Garden forever he should not partake of the fruit of the tree. But He also gave them a greater commandment; that they must multiply and replenish the earth; something they could not do if they remained in the garden.
The concept of free agency and choice has been an eternal principle from the very beginning. It was there in the pre-existence when we made our choice to follow Christ's plan; it was there when Jesus chose to give up His life to save us; it is with us now as we work out our salvation; and it was there when Adam and Eve chose what they decided was the way things had to be. As God said;
"Nevertheless, thou mayest choose for thyself, for it is given unto thee;" (Moses 3:17).
The fall of Adam was not an accident nor was it an obstruction to God's plan. God knew that Adam would choose the way he did, but it was still important that Adam make the choice for himself, and not just be forced to do it.
After Eve was beguiled by Lucifer to partake of the fruit, Adam concluded that God’s command to remain with his wife (see Moses 4:18) was more important than His command to abstain from the fruit; so they made the decision to nolonger stay in the Garden of Eden. Thus "Adam fell that men might be" (2 Ne. 2:25).
Adam's choice was not one that could result in committing a sin, for since he did not yet comprehend good or evil, he did not have the capacity to commit sin. It was simply a transgression; an act that was formally prohibited by God if they wanted to stay in the garden, but not inherently wrong.
Even though it might be hard to understand why God did it this way, we should take comfort in the fact that God's will prevailed. Adam and Eve ultimately kept the first commandment He gave them, to multiply and replenish the earth, and because of that we were able to come to earth and work towards eternal life with God.