Relativity is as much belief in supernatural order as radiation poisoning is divine retribution. I don't even want to think how ignorant one must be to define religion that way, or single out Islam and Buddhism.
The book is "A Brief History of Mankind" and every chapter I read was as bad as this, full of conjecture drawn from mere bits of evidence, grasping at straws to make grand claims without ever indicating a mechanism for how a thing came to be. Even bad historians make the effort to find a proponderance of evidence, while this guy's methods resemble a certain psychologist.
My main issue was with the "belief" and "order" parts so I didn't even notice that I wrote it wrong. In science, there's no concept of order or chaos. These are results of how humans process information and perceive their environment.
Relativity, or any other theory with predictions supported by experimentation are facts, not the order of things. If we find something that might be colloquially called out of order, this means the theory ought to be amended or replaced. This has no bearing on the actual phoenomenon, which was never in contradiction with the occurrance. They also don't require belief beyond the acceptance that our observations ar egenerally accurate.
I should go into why I find his classification of religion entirely off but I'm too sleepy to muster the energy.