During the release period of episode III, Wired magazine had an interview with George Lucas and the interviewer asked him about the idea behind the Force, how he came up with it. He quoted to Lucas something from a film (or a short film, can't remember) by a particular filmmaker (again, I can't remember his name) who inspired Lucas:

"Many people feel that in the contemplation of nature and in communication with other living things, they become aware of some kind of force, or something, behind this apparent mask which we see in front of us, and they call it God."

I can't remember Lucas' exact response when asked about it, but he hinted that yes, that is one of the things which inspired the Force in Star Wars. Also, notice the word "force" in it. More likely than not, that is where Lucas got the idea to call his Star Wars jedi religion "The Force".

So, there you go. I found that quote to be quite insighful into the mysteries of life, something which you can use to describe the concept of the Force, and I thought it would be a very interesting bit of Star Wars trivia to share with all of you.