Satan, as seen in Codex Gigas. Demons are generally seen as evil beings, and Satan as greatest of these (in the Christian tradition).
She writes: ‘Out of evil, much good has come to me. By keeping quiet, repressing nothing, remaining attentive, and by accepting reality—taking things as they are, and not as I wanted them to be—by doing all this, unusual knowledge has come to me, and unusual powers as well, such as I could never have imagined before.
I always thought that when we accepted things they overpowered us in some way or other. This turns out not to be true at all, and it is only by accepting them that one can assume an attitude towards them.
So now I intend to play the game of life, being receptive to whatever comes to me, good and bad, sun and shadow that are forever alternating, and, in this way, also accepting my own nature with its positive and negative sides.
Thus everything becomes more alive to me. What a fool I was! How I tried to force everything to go according to the way I thought it ought to!’ ~A Letter from Dr. Jung’s patient as reproduced in the Commentary of the Secret of the Golden Flower.