Norman Mailer, I suspect, is given to the thinking of religious existentialists and considers that the Ultimate Nature of God is unknowable and that, if we're created in His likeness and have our best attributes due to his nature, it's neither unreasonable nor blasphemous to think of Him as resembling his children more closely than one would suppose. A good amount of that is that God continues to learn , continues to grow, and is one to come up with new ideas about what do with this problematic earth-bound existence he gave us, and that he's inclined to change His mind.
Since God is creation, and creation includes the constancy of change, it is plausible, feasible, very attractive to regard the notion of God sticking to a Master Plan, and that He micromanages the affairs of each soul that entreats Him in crisis as wishful thinking; the desire to have phenomena explained as being meaningful in a Grand Scheme has us undermining the idea that we are God's servants who, subtly, want to control the definition of a Higher Power as being rigid, fixed, useful for a population's sense of linked continuity , and useful as well for political purposes for those who use the few words of The Bible and have them mean their opposite.
This Static God is at odds with the world He created, which by its nature is sustained by dynamic change. God is subtler, I think, than the cloud-bound bully that millions have been forced to endure from childhood until an accumulation of experience forces one to change, lest one become rigid and fixed as the God they grew up with, without joy and without value to one's fellows.