But "whatever God does is automatically good" might suggest that he is capricious. And maybe if he does evil things, it doesn't matter because we've got rule number one: he is God. Christianity doesn't teach that. Christianity holds that evil originates with human choice to be less than "true" men.
It's too bad we are prone to misunderstand the purposes of nature with that of God and man.
How could God do evil things unless there is an external concept of evil that God can be measured against?