Isaiah 8:19 (b) Spirit mediums, necromancers and others deal with spirit and work in the dark. They cannot see plainly. Therefore, this word is used. It also indicates that there is no intelligence in what they say they see. They cannot see fully nor clearly. Also, the language they use is not familiar. They do not speak plainly. (See also Isaiah 10:14, where it indicates the people could not complain).