And yet people who have held such beliefs have, time and time again, demonstrated intelligence that is comparable to people who don't.
Just going by architecture alone, Stonehenge. The Pyramids. Vast cities.
Christian monks were the pioneers of the fields that would become the modern sciences. (Contrary to that stupid myth that we were somehow "making so much progress, then Christianity showed up and set us back").
But consider this: rain makes things grow. Here's an aspect of Father Heaven that Christianity did a pretty good job of erasing from European Lore: when it rains, that's Father Heaven and Mother Earth having sex. Rain is the Sky God's Holy Semen.