Adam added a fence around the original prohibition against eating the fruit and told Eve they must not even touch it.
When Eve told this to the snake, she did not mention anything about Adam adding this fence. (Perhaps Adam never told her it was a fence? GS) She said they cannot eat from it or touch it lest they die. The Midrash explains that the snake caught her on this distortion, pushed her into the tree and told her that just as she didn’t die from touching the tree, so too she won’t die from eating its fruit.
This is the danger of exaggerating a rabbinical fence. Fences are important, but they must always be recognized as fences.
That same Midrash puts it this way: When a person builds a wall higher than it should be it will fall down on the produce it was designed to protect.
Beraishis 3:2-3, Pages 74-75
