Charles Ellicott Commentary Job 24:16

"In the dark they dig through houses: They shut themselves up in the day-time; They know not the light." — Job 24:16 (ASV)

Which they had marked for themselves in the daytime. —Or, as some understand, they seal (i.e., shut) themselves up in the daytime. It is said that it is still the custom in Eastern cities for such persons to endeavour to obtain access to the harem in female attire.

They know not the light. —Compared with Job 24:13, shows strongly the different usage of the expression in the two cases.