See also: Forty Hadith (Ayatollah Khomeini). Forty Hadith, arbaʿīniyyāt is a subgenre of the Hadith literature. As the name indicates, these are collections containing forty hadith related to one or more subjects depending on the purpose of the compiler.[1] The best-known example is by far Imam Nawawi's Forty Hadith, aiming to include all the fundamentals of the sacred Islamic law.