The sunnah refers to the habits, practices, words, and decisions of the Prophet Muhammad in Sunni Islam, and of the Prophet and the twelve imams who succeeded him as leaders of the Muslim community in Shi’a Islam. Hadith are written records of the Sunnah as validated by early Muslim scholars, though the terms are often used interchangeably as hadith are now the only source for understanding the sunnah. Sunnah is an Arabic word meaning “habit.” It was a pre-Islamic Arab tradition to record a person’s sunnah after death, and this tradition carried over to the Prophet as the Arab world adopted Islam. The sunnah is spiritually important to Muslims as a guide to living, as the Qur’an contains numerous injunctions to believers to follow the example of Muhammad.
Though Islamic scholars first consult the Qur’an for guidance, many questions regarding personal, family, and political affairs require insight from the sunnah, which covers an immense amount of material thanks to Islam’s thorough collections of hadith. However, the use of the sunnah is sometimes less straightforward than that of the Qur’an, as Sunni and Shi’a Muslims accept different hadith as genuine, and even different scholars within the same denomination may differ on the authority of a given hadith. In fact, different canons of hadith are one of the main points of division and tension between Sunni and Shi’a. Abiding by the sunnah is an important aspect of Muslim life because believers hold that one gains the love of God by living in the exemplary manner in which Muhammad lived.