Don't worry if people start vanishing, and someone claming to be God and someone claming to be the Devil show up on Earth to do battle we got Stargate Command to sort it all out. They deal with weird ass sh*t like this all the time.
No doubt their solution will involve time travel or perhaps some sort of ancient alien device.
If SG-1 had a nickel for every time they killed someone claming to be a god (or in a few cases the devil) or saved the world they could retire.