Unchanging History

Humans hate change. And if any sort of "organization" actually likes change, it is probably young and unestablished. Why must a historical religion be "purer" than its modern form, for example? Perhaps it came from a time when change was necessarily a bad thing. A comfortable routine of having 3 square meals was a good thing. Suddenly having 5 meals a day and starving for the next 3 would probably be undesirable. Over time, humans became more and more comfortable with the idea of stagnation in stability. Perhaps that is why religions never wish to change with time, and why some remarkably illogical things are still being clung to.