Psalm 103: As Far as East from West

The psalm begins by telling the soul not to forget, which implies forgetting is the default.

Then the measurement: as far as the east is from the west, so far has he removed our transgressions.

North and south have ends — you can reach a pole and start coming back. East and west do not meet. The image was chosen for a distance that cannot be closed.

And the reason given is not our improvement but that he knows our frame, and remembers that we are dust.