One of the recurring points that Armstrong brings up is that people who are on the verge of great change in their society or culture tend to cling to their old faiths as a reaction to the change. Basically people don't deal well with new things. It takes us a long time to adjust and to find our footing in our new worlds. We have to rewrite much of what we know so that we can continue to function.
So people at first tend to cling to the old forms of their faiths. Even those who might not have been particularly religious before will become so in an effort to find something solid to hold onto while the rest of the world shifts. But many of them find (sometimes quickly and sometimes after long periods of being conservative in their attitudes) that as they adjust to the new world around them that that old forms of their faith no longer work. They don't fit with the world around them. Not whole hog dissolution of their faith but more that certain aspects of it don't work with the new mindset - slavery, for example. It's accepted at the very least in the Bible and the Qur'an if not outright encouraged. But it's no longer acceptable to have the attitude that it's okay to own other people. So do we reject the world's view that all people are equal regardless of their race and reinterpret the scriptures to fit with that view or do we reject the world and cling to the idea that the world of the scriptures was good and perfect so clearly some people are born better than others based solely on their race and the color of their skin?
Thoughts? Should religious understanding change? Can you think of any 'forms' in your faith that have changed because of the changes in society or things that need to be changed?