Eric, I find this most interesting - on the first level, I have done the interior of a church very recently - think I may have posted the image in the gallery. The church was empty, sans myself so aside from the feeling of excitement to work inside with no one there, I began to look around. Now, I am prone to immediately start to listen, there was an old pipe organ, for the voices then as I looked from the front to the rear I tried to 'see' all the people that had been there. What were the smells, what did they wear, because of the area I know they were hard working peoples.
From your image I think I would take a different view, was in Chiamyo, NM last month - this is were many come for 'holy' dirt that cures. Have been there before, and each time it was like you said - people come and go, then slip away. Your image is a snapshot (and no I don't mean like a snap shot, but a point in time) of these peoples lives. They felt compelled to be there at that moment, something pulled them to that place and for the split second in time you were able to capture the moment. Not unlike when young Mr. Kennedy stepped out to salute his fathers casket, or the many other 'moments' that have been so powerfully captured by the medium.
Did not really look to see what the technical aspects of the image are, just the fact that it was a moment in time...oh, and while not really religous by nature, a church without people is just a building, the people ARE the church..but that is just the way I feel.
Hope this is what you were looking for.