And the mean man boweth down, etc. So Ewald and Kay; but most other commentators render, "Therefore shall the mean man be bowed down, and the great man brought low, and thou shalt not [or, 'canst not'] forgive them" (Rosenmüller, Lowth, Gcsenius, Knobel, Cheyne).
The transition from narrative to threatening comes best at the beginning of the verse.