User blog comment:DeathGodPrayer/Talk About What You Want!/@comment-24098614-20140214120353/@comment-1359322-20140215101548

First, I don't think God created the Sacred Gears to save the world, he create the Sacred Gears to protect his own religion only, since without Him around, other religion might attack and eliminate his religion.

Second, it's because God doesn't know what will happen in the future that he created the Sacred Gear system, so that it could be used to prevent the unknown disasters that will occur after His death.