I think what is important to acknowledge is that what we know about God is what another human has experienced and recorded. I don't know if God exists or not, but what we know of him/her is the result of another persons experience from centuries ago.
This leaves raw religion susceptable to change, for good and bad. Here are two examples. Much of the biblical scrolls were hidden away in a desert in Egypt. They were banished by the early church as they empowered women and challenged idea's about Jesus' ascention. This has obviously influenced much of what we read in the bible.
Another example is from 12/13th Century France-Languedoc. A new 'heritcal' movement was developing, Catharism, which basically was just a simplified version of Catholicism. They believed in family life, women were more equal therefore, poverty, and two Gods. They claimed the Catholic Church was too rich and the way to Heaven was through poverty etc. They were eventually killed, but their idea's drew in great interest and opened up religion to more people in that area.
These example show that religion is controlled by man. It applies to any religion. God may exist, but how we understand him/her and praise him/her is the product of humans. It can change over time by the will of people or by the will of one person. Look at Henry VIII. He created a whole new version of the Church, and became a Protestant, just so he could divorce his wife!
In relation to belly dancing, it is easy to see how it can be viewed as 'sinful' due to the image it has in society. Religion influences peoples view of things. If you've grown up in a very strict religious environment where you are taught traditional values, and celibacy it must be hard to appreciate how belly dance could be unsinful. People moving their body in a sensual way must be intimidating. It's like if I was landed in a stripper bar. I wunt know what to do, or where to put myself.
Well that turned out longer than I'd planned. Hope it made sense, and I haven't offended anyone.
Cyas
Sara