Okay, let me try again. Assuming, of course, semi-factual status of the allegory of the apple and Eden, here is why we DIDN't fail and why God meant for us to eat the apple:
1. God created all the animals and put them into the garden, living happily and freely together without guile, spite or subterfuge. Then he creates Mankind, specifically states that Man is the master of beasts, and bestows free will on man alone. No other animal is given this gift.
2. God, as an omnicient creator or at the very least working from a divine plan, would not have bestowed such a gift on humanity if he did not intend them to ever use it. However, in the Garden of Eden everything is free and avasilable, and ripe for the taking. With such an easy life there is no need to exercise free will in the slightest. In that regard, God's creation is a failure.
3. God clearly wants Adam to exercise free will, but he can't force him to it or it's not free will at all. So God pulls Adam aside and says, "Listen, d00d, you can eat anything in this forest EXCEPT that tree right there. If you do, you'll surely die." Remember, God has given man this fabulous brain and expects him to use it. According to the church, Adam is supposed to obey God and leave the tree alone.
WRONG. Obedience is not the most primal exhibition of free will. Disobedience, a deliberate and willful act contrary to the "rules", is the most primal version of free will there is. God showed Adam the forbidden fruit, planted that sucker square in the middle of the Garden, and warned him of dire consequences should he disobey.
Yet, why plant the thing in the center at all, if he didn't want to test his Children? Any parent knows that the quickest way to get a child to do something is to forbid it. And God was omnicient. He as much as led them to it by their noses.
So Adam and Eve eat of the "tree of knowledge". Interesting name for a tree which supposedly brings death. Do they die? No. They Become aware. Aware of the need for clothing, aware of the need for shelter, aware of the need for self preservation. In other words, God the Father has taught them exactly what every parent should: self-sufficiency in the face of adversity. In God's own words:
"They have become like unto us." At the moment Adam disobeys God the Father, he enacts the drama played out by every teenager the world over. He ceases to be a child and becomes a man by defying the laws of his father before him. By utilizing the free will God gifted him with.
Further evidence. When God knows what has occured, he goes to find Adam, but instead of calling him on the carpet he asks where he is. God knows full well where Adam Is: He's God for crying out loud. But he's giving Adam yet another opportunity to exercise free will through guile and deception. If Adam can create a falsehood in order to preserve his safety, he has passed another survival test. Again, every child passes such a milestone in his or her development, and at its basest level this is the ability to tell right from wrong. In order to lie about one's actions, one must first recognize that an error or crime has been commited.
So once Adam and Eve pass this test, they are proven fit for survival outside the protection and safety of the Garden. This has been God's intention all along. Why else would he make such a marvelous toy, if not to see it reach its full potential? He also bestows one final gift on mankind, though religious history has incorrectly labelled it a curse: the gift of childbirth. Eve was not a woman in the garden; knowledge of Lust came with the tree. In reality, though, God's "Curse" was the ultimate diploma for his children. "Go forth" he said, "And be fruitful, and multiply." In other words, do as I did and create life. "Now they are like unto us." God meant it exactly that way...