Why, of all the rules one might make—the violation of which might result in the fall from grace and expulsion from the Garden—did God make his one forbidden thing the willful seeking of this Knowledge of Good and Evil?

After the sentencing of Gen 3:16-19, one might well be left with this question. The short answer is that, if man is to live in God’s presence, he must be holy; and, in a childlike state, he can remain holy only by following God’s will and thus utterly rejecting all acquaintance with the blessings and curses of a life that is independent of God. As soon as Adam sought such knowledge, God had to exclude him. But what that means, in other words, is that a minimal prerequisite of any sinning, in Adam’s original sinless state, is to reject God’s will; if he was never did that, then he could never sin. So, really, it did not matter what particular activity was forbidden; it could have been playing ping-pong, or working on the sabbath, or speaking too loudly. Adam’s mere daring to do the forbidden thing meant he was no longer willing to follow God’s will, and hence be utterly dependent on God. And that activity, whatever it might be, would thus be deemed “of the Knowledge of Good and Evil,” because such knowledge would be the consequence of partaking in the forbidden thing (game, work, or speech).