Here is an example of a simple painting that expresses distance. The center of interest is of course obvious but the eye is directed even more to that area because the darkest darks and the lightest lights are next to each other. Had that patch of sunlight in the distance been way over to the right, the eye would tend to bounce back and forth between those two points. As a general principal, the contrast should be greater in the area of the focal point.
This also expresses another principal. A painting should have a dominant area of color (the bluish sky), a sub dominant (the warm reddish earth and tree) and an accent (the yellow distant marsh)
These are principals, not rules.