Originally mentioned in a
Talmudic context, the Holy Fool, or
Chasid Shoteh, appears in
Sotah 20a and 21b, where he is included in the list of people who are responsible for the destruction of the world. The term is not at all complementary, it refers to someone whose
piety is so strong that he ends up commiting a grave
sin in order to avoid commiting a minor one. The most famous example of a holy fool is a man who doesn't rescue a drowning woman, because he is
forbidden to look at her.