God doesn't want the world to know that, he is the real culprit behind each and everything(INCLUDING EVIL) and so, he asks us to blame the devil for the things which are regarded as EVIL. But in reality, even the devil is God's creation. God wants to show himself as a hero and he wants to show us that, his creation is PERFECT. He wants us to get distracted from the fact that, even the devil was his own creation, which turned out to be IMPERFECT. God is the main deceiver. He is the real culprit behind all the things(be it good or EVIL). Don't just follow your religions blindly. In reality, good and evil are part of the same divine nature.