I’m not sure of the historical basis, perhaps another person here can expand on that. However, I do know that prayer is done differently in various cultures. I’m pretty certain that our style of prayer is just that, a North American style of prayer. For example, I know of Christians in the Middle East who pray with their eyes open and hands open, similarly to how Muslims pray.
A teacher of mine once told us to practice what he called “eyes open prayer” and I’ve done that ever since. It makes sense to me that I would look at people that I’m praying with, that as I’m praising God I’d look at the people I’m praising God for.
This is just speculation, but my initial thoughts are that our style of prayer has been influenced by individualism (i.e. closing your eyes “nobody but you and God) and theatrics.
The inside reflects the outside and the outside reflects the inside. Looking at how we physically pray can be a good indicator for what we actually believe about prayer. The best way to find out what people actually believe is to watch their actions!
What does everyone else think?