The Sunnah is one of two sources of Islamic law.
 The term al-sunnah then eventually came to be viewed as synonymous with the sunnah of Muhammad, based on hadith reports
 Ibn Qutaybah (213-276 AH) distinguished between:Sunnah "brought by Gabriel";sunnah from "Muhammad's own ra'y and is binding, but subject to revision";"non-binding sunnah", which Muslims are not subject to "penalty for failure to follow"

