hold on there... (spoiler!)
If you tip earth into a hole in the ground, doesn't it just fill up? What I'm saying is, to cover the church so the soil doesn't fill the void then you need to create a roof. But if there's a roof, then you wouldn't have any light for the last scene where you see the earth being piled on top to re-bury the church. The only way they could have achieved that effect was to build a clear roof, then pile the soil on top of that.
Oh well...
...it's just another dumb film, get over it.