The snake is a tempter in the Garden of Eden story, but hardly the devil. Rather the snake is the symbol of wisdom (the Goddess' wisdom in ancient tradition). Your interpretation that this is a devil is anachronistic. As another commenter has pointed out, gaining wisdom (knowing good from evil) was something that was supposed to happen. I will add, who better to facilitate this than Her symbol of wisdom. I came to the conclusion that the Adam and Eve story may be anti-Yahwist as "He" is shown to be a liar. In 2:17 he says Adam will die the same day he eats from the tree.  Of course there is some confusion as to which tree is forbidden, but even so a lie? The serpent was correct, that eating of the tree of the knowledge of good and evil did not bring death. Rather, it was not having access to the tree of life that brought mortality. Interesting that Yahweh is the jealous and anti-life god. Recall the Tree of Life was Hers at that time. Re-read the story in its historical context.