“The jealous is possessed by a "fine mad devil" and a dull spirit at once.”
Johann Kaspar Lavater (1741–1801) Swiss poet
No. 345
In William Shakespeare's The Merry Wives of Windsor, Act 5, sc. 1, Falstaff says that Mistress Ford's husband has "the finest mad devil of jealousy in him".
Aphorisms on Man (1788)