High Quality Content by WIKIPEDIA articles! Sunnah is an Arabic word that means habit or usual practice. The Muslim usage of this term refers to the sayings and living habits of Muhammad, the prophet of Islam. Recording sunnah was an Arabic tradition, and once people converted to Islam, they brought the tradition to the religion. The Sunnah of Muhammad includes his specific words, actions, and practices. It is significant to the spirituality of Islam because it addresses ways of life dealing with friends, family, and government.