This was used to cover the walls of houses (Lev. 14:42-48; Dan. 5:5); and was also spread on large stones, on which the law could be inscribed (Deut. 27:2-4; Josh. 8:32). It may have been compounded of different substances for divers purposes. In Isaiah 38:21 plaster is used in a medical sense as spread on a boil.