When one tries desperately to be good and wonderful and perfect, then all the more the shadow develops a definite will to be black and evil and destructive. People cannot see that; they are always striving to be marvellous, and then they discover that terrible destructive things happen which they cannot understand, and they either deny that such facts have anything to do with them, or if they admit them, they take them for natural afflictions, or they try to minimize them and to shift the responsibility elsewhere. The fact is that if one tries beyond one's capacity to be perfect, the shadow descends into hell and becomes the devil.

Carl Jung. Visions. 1976.