There are several religious beliefs that are delusions. We have been led into a Babylonian captivity by the doctrines and traditions of men. (2 Th. 2:10-12; Is. 66:4) These two passages are the only places the word delusion(s) is used in the entire Bible. The Hebrew word for delusions is taaluwal – caprice or any fanciful idea(s). The Greek word for delusion is plane – fraud, deceit, fraudulence, or error. Why would God choose or send us delusions?
Precious Sheep Of Renown 
According to certain religious writings, God may permit delusions as a kind of punishment or as a test of a person’s faith.