Looseth — He freeth them from that wherewith they bind their subjects to obedience, their power and authority, and that majesty which God stamps upon kings, to keep their people in awe. Girdeth — He reduces them to a mean and servile condition; which is thus expressed, because servants did use to gird up their garments (that after the manner of those parts were loose and long) that they might be fitter for attendance upon their masters: he not only deposes them from their thrones, but brings them into slavery.
Related Commentaries of Job 12:18
Job 12:18
18 He looseth the bond of kings, and girdeth their loins with a girdle.