I - Introduction
The noble Sunnah is part of the revelation given to Prophet Muhammad and it is for this reason that some scholars call it, 'the half-sister of the Quran.’ Sunnah is also similar to the Quran in authority and power over Muslims’ actions and practice and together they are the total source of this religion and its full foundation.
This position and role of the Sunnah can easily be appreciated when considering the Quranic verses talking about the Messenger and his role, for Allah, Almighty, not only sent Muhammad as the bearer of His miraculous Book, the Quran, but also as an example that must be followed by the believers. Allah Says (what means): “There has certainly been for you in the Messenger of Allah an excellent pattern for anyone whose hope is in Allah and the Last Day and [who] remembers Allah often.”[Quran 33: 21]
The role of Muhammad as a messenger was to deliver Allah’s message and establish His religion, Islam, by conveying His revealed Words or the Quran by teaching and explaining it through his words, actions and confirmations, orders and prohibitions regarding religious matters or general life guidance which constitute his Sunnah. Allah Says (what means): “…And remember the favor of Allah upon you and what has been revealed to you of the Book and wisdom by which He instructs you. And fear Allah and know that Allah is Knowing of all things.” [Quran 2: 231] and (what means): “And if it was not for the favor of Allah upon you, and His mercy, a group of them would have determined to mislead you. But they do not mislead except themselves, and they will not harm you at all. And Allah has revealed to you the Book and wisdom and has taught you that which you did not know. And ever has the favor of Allah upon you been great.”[Quran 4: 113]
It is clear from these verses that the Messenger taught the believers in the matters of religion something other than just the Quran, and that something (referred to as 'Hikmah') is nothing other than his Sunnah as has been agreed upon by all scholars.
These as well as other verses tell us that the Prophet taught both the Quran and the Sunnah, and that both of them are revelations from Allah (although in different forms) for mankind's instructions. It would be meaningless to differentiate, in terms of obedience, between Allah and someone appointed by Him as His Messenger, required everybody to obey him, and guarded him from mistakes in relaying Allah's commandments. Allah Says (what means): “Your companion [Muhammad ] has not strayed, nor has he erred. Nor does he speak from [his own] inclination. It is not but a revelation revealed.” [Quran 53: 2-4]
Thus the Sunnah constitutes, as a whole, a binding legal source in all matters for which Muslims need guidance and judgments. As such, the accepting of the authority of the Sunnah is fundamental to one's faith and is directly related to the pillar of believing in the prophethood of Muhammad .