Sanctimonious, pretending moral superiority. This term comes from the Bible (Isaiah 65:5), where the prophet, speaking of sinners, holds that they say “Come not near me, for I am holier than thou.” The term is often used as an adjective (and hyphenated: holier-than-thou) as in Sinclair Lewis’s novel Babbitt (1922), “But I don’t want you to think you can get away with any of that holier-than-thou stuff.”