Sunnah and Islam

Passages in the Qur'an command that the prophet be followed, such as 3:32 ."Obey God and His messenger".[6] For Muslims the imitation of Muhammad helps one to know and be loved by God: one lives in constant remembrance of God.[2]
Shi'a Muslims do not use the six major hadith collections followed by the Sunni. Instead, their primary collections were written by three authors known as the 'Three Muhammads'.[7] They are: Kitab al-Kafi by Muhammad ibn Ya'qub al-Kulayni al-Razi (329 AH), Man la yahduruhu al-Faqih by Muhammad ibn Babuya and Al-Tahdhib and Al-Istibsar both by Shaykh Muhammad Tusi. Unlike Akhbari Twelver Shi'a, Usuli Twelver Shi'a scholars do not believe that everything in the four major books is authentic. In Shia hadith one often finds sermons attributed to Ali in The Four Books or in the Nahj al-Balagha.
Traditional Muslims believe that the sunnah is justified by verses such as "A similar (favour have ye already received) in that We have sent among you a Messenger of your own, rehearsing to you Our Signs, and sanctifying you, and instructing you in Scripture and Wisdom, and in new knowledge.(2:151)[citation needed] The verse "Verily in the messenger of God you have a good example for him who looks unto God and the Last Day and remembers God much". (33:21), further emphasizes that Muhammad's mission is to teach and exemplify The Qur'an, not just to relate its verses and leave. Muhammad was not to be worshipped or deified but his role was to deliver The Qur'an with comprehensive explanations of how to live according to the Qur'anic guidelines preserved in Sunnah. The teachings of "wisdom" have been declared to be a function of Muhammad along with the teachings of the scripture.[8]
For a better understanding of "wisdom" (hikmah), one can refer to The Quran itself. For example, verse 4:113 states; "God reveals the Book (i.e. the books of revealed religion, especially The Qur'an) to you, and wisdom, and teaches you that which you did not know. The grace of God towards you has been very great". Verse 2:231 states; "And remember God's grace upon you, and that which He has revealed unto you of Scripture and wisdom whereby He exhorts you". Verse 33:34 states, "And bear in mind which is recited in your houses of the revelations of God and of wisdom".
Some have said that "wisdom" here is simply another name for sunnah. Therefore, along with divine revelation the sunnah was directly taught by God. Modern Sunni scholars are beginning to examine both the sira and the hadith in order to justify modifications to jurisprudence (fiqh). The sunna, in one form or another, would retain its central role in providing a moral example and ethical guidance.