Dr. John Piper recently gave the question some fresh thinking, which he shares in an episode of Ask Pastor John:
The function of the tree of the knowledge of good and evil is to make sure that the pleasures of all the other trees in the garden are supremely pleasures in God.
The command went like this: “And the LORD God commanded the man, saying, ‘You may surely eat of every tree of the garden, but of the tree of the knowledge of good and evil you shall not eat, for in the day that you eat of it you shall surely die’” (Genesis 2:16–17).
So what was God saying in prohibiting the eating of one tree out of a million trees? He was saying, “I have given you life. I have given you a world full of pleasure, pleasures of taste and sight and sound and smell and feel and nourishment. Only one tree is forbidden to you. And the point of that prohibition is to preserve the pleasures of the world, because if you eat of that one you will be saying to me, ‘I’m smarter than you. I am more authoritative that you. I am wiser than you are. I think I can care for myself better than you care for me. You are not a very good Father. And so I am going to reject you.’ So don’t eat from the tree, because you will be rejecting me and all my good gifts and all my wisdom and all my care. Instead, keep on submitting to my will. Keep on affirming my wisdom. Keep on being thankful for my generosity. Keep on trusting me as a Father and keep on eating these trees as a way of enjoying me. There are 10,000 trees, every imaginable fruit. Just go eat. Be thankful. I have given them to you and see them as expressions of my goodness and savor them that way.”
And Satan comes along, and he takes that arrangement and says, “Hey, Eve, the meaning of that arrangement is: God is selfish. God is stingy. He is a skinflint.” So he took the prohibition of one suicidal tree and treated it as a prohibition of everything.
So the issue of the tree is this: Will we keep looking to God as the giver and lover and treasure of this garden so that all our eating is thanking and all our savoring is a savoring of God? Will we keep on experiencing every one of these tastes as a tasting of something like what God is, and in that sense a tasting of God? Will we keep on enjoying God in the enjoying of the trees?
That is what the forbidden tree was there to test.
I think a lot of people try to set that up as merely arbitrary: Will man obey? Or will he not obey? And they don’t put it in the context of his fatherly care and all the goods that he has given. I don’t think it is arbitrary like that.
It was a warning. “If you choose independence instead of God-dependence, you will lose the pleasure of the garden and God with it.”
“If you keep trusting me and enjoying me as your greatest delight and highest treasure, you will have this garden and I will be the pleasure of all your pleasures.”
The forbidding one tree is a way of securing that the pleasures of all the other trees in the garden are supremely pleasures in God.