What does "cease and desist" mean?

Stop, leave off doing something, as in: “Bliss excavated at least once on his own and Dr. Brand ... told him to cease and desist” (Douglas Preston quoting Frank Hibben, The New Yorker, June 12, 1995). This legal term is a redundancy, since cease and desist mean virtually the same thing, but often appears in legal documents to avoid possible misinterpretation. [c. 1920]