In the garden, Adam and Even had perfect bodies– immortal– no sickness or death. They were like children. Innocent. They had forgotten life before mortality. They also could not have children. When God created them, he gave them two commandments:

1. Here’s the Garden of Eden. Lots of good fruit here. Eat whatever you want. But you are commanded not to eat of this one particular tree. It’s the tree of knowledge of good and evil. If you eat that fruit, you will become mortal.
2. Multiply and replenish the earth, start a family, learn to be parents, and be happy (men are that they might have joy).

But, wait, these two commandments conflict with each other!