Is God willing to prevent evil, but not able?
Then he is not omnipotent.
Is he able, but not willing?
Then he is malevolent.
Is he both able and willing?
Then whence cometh evil?
Is he neither able nor willing?
Then why call him God?
- Epicurus
This statement was put forth by the great philosopher Epicurus when Christianity was a new concept in the world, and the idea of one god rasied eyebrows. For this instance, in almost all polythiestic culture, no one god is all powerelful. Some may be more powerful than others, but as far as an all powerful god, they're just aren't any (in polytheism). This was a simple enough conclusions to understand, for if one god was good, and evil happend, one could simply blame the malicious god.
Now I leave this paradox up to you to interpret for yourself. However the point is still very relevant.