''Nass'' () is an

Arabic Arabic (, , or , ) is a Central Semitic languages, Central Semitic language of the Afroasiatic languages, Afroasiatic language family spoken primarily in the Arab world. The International Organization for Standardization (ISO) assigns lang ...

word variously translated as "a known, clear legal injunction," a "divine decree", a "designation", "written law" as opposed to unwritten law, "canonical text" that forbids or requires, a "textual proof". In

Shia Islam Shia Islam is the second-largest Islamic schools and branches, branch of Islam. It holds that Muhammad in Islam, Muhammad designated Ali ibn Abi Talib () as both his political Succession to Muhammad, successor (caliph) and as the spiritual le ...

(

Twelver Twelver Shi'ism (), also known as Imamism () or Ithna Ashari, is the Islamic schools and branches, largest branch of Shia Islam, Shi'a Islam, comprising about 90% of all Shi'a Muslims. The term ''Twelver'' refers to its adherents' belief in twel ...

and

Isma'ili Ismailism () is a branch of Shia Islam. The Isma'ili () get their name from their acceptance of Imam Isma'il ibn Jafar as the appointed spiritual successor (Imamate in Nizari doctrine, imām) to Ja'far al-Sadiq, wherein they differ from the ...

), ''nass'' refers specifically to the designation of an infallible

Imam Imam (; , '; : , ') is an Islamic leadership position. For Sunni Islam, Sunni Muslims, Imam is most commonly used as the title of a prayer leader of a mosque. In this context, imams may lead Salah, Islamic prayers, serve as community leaders, ...

by a previous infallible Imam.

References

Twelver theology Islamic terminology Ismailism {{shia-stub fa:نص