Because there is no god, and people like Waterrock have to perform cognitive gymnastics in order to maintain belief that a flawed holy book actually was written by an invisible super being, so they can maintain a belief in that being, which gives them security, a feeling of superiority, or who knows what else.
"...the God I don't believe in is a good God, a just God, a merciful God. He's not the
mean and stupid God you make him out to be." - Lt. Scheisskopf's wife, from Catch 22 by Joseph Heller