Charles Ellicott Commentary Job 18:21

"Surely such are the dwellings of the unrighteous, And this is the place of him that knoweth not God." — Job 18:21 (ASV)

Dwellings of the wicked. —That is to say, of the wicked man. As Bildad deliberately uses the singular here, there can be little doubt that he just as deliberately intended this terrible and cruel picture to represent Job himself.