Salaamu Alyckum
Sunnah means the way of the Prophet Muhammad (peace and blessings be upon him). It includes everything he said, did, and approved of. We know the Sunnah from the statements called Hadiths that have been handed down from the Companions of the Prophet.
Opposing Mohameed and changing his Sunnah is misguidance and innovation. It is threatened by Allâh with utter bereftness and punishment.
Islamic Law is taken from the Qur’an and Sunnah. The Sunnah in this sense both explains the Qur’an, and also gives additional rules and guidance. The Qur’an in many places tells us to obey the Prophet (peace and blessings be upon him), and thus it is wrong—as some deviant sects claim—that the Qur’an is sufficient and that we do not need the Sunnah.
According to Islamic jurists, the Sunnah is second to fard. Fard means something is obligatory and it must be done; to neglect it without any excuse is a sin. The Sunnah is divided into confirmed (Sunnah mu’akkadah) and optional (Sunnah ghairmu’akkadah). The confirmed Sunnah also should not be neglected, though it is not as important as the fard. The optional Sunnah is recommended, but if someone neglects it, there is no sin or blame on that person.
For example :Sunnah Prayers refer to the additional ritual Prayers (Salah) that are recommended before or after the obligatory (fard) Prayers. It is not necessary to perform these additional Prayers, but it is highly recommended to do so. This is because we will be rewarded for imitating the Prophet (peace and blessings be upon him), and because, on Judgment Day, those Sunnah Prayers will compensate for any obligatory Prayers that were missed or not accepted. For each of the obligatory Prayers, there is a certain number of rak‘ahs of Sunnah Prayer to be performed before and or after the obligatory ones.
Sunnah can also refer to those things that the Prophet (peace and blessings be upon him) did in order to bring himself closer to Allah, in contrast to those things that he did simply out of habit or custom. So, for example, the Prophet (peace and blessings be upon him) slept on a simple mat out of habit or custom. We are not required to follow him in this. But he also went to sleep on his right side and advised us to do the same. Thus sleeping on the right side is a Sunnah, something he did to please Allah.
The way of the Prophet Muhammad (peace and blessings be upon him) is the way that should be followed by Muslims.
Allâh says, "Let those who oppose his command beware of a trial that might strike them or a painful punishment that might befall them." (24:63)
and "Whoever splits from the Messenger of Allâh after the guidance is clear to him and follows other than the path of the believers, We shall entrust him to what he has turned to." (4:114)
Allâh says, "O you who believe, obey Allâh and His Messenger ... "(8:20)
"Say: obey Allâh and obey the Messenger ... " (24:54)
"Obey Allâh and the Messenger and perhaps you will be shown mercy." (3:132)
"If you obey him, you will be guided ... " (24:54)
Whoever obeys the Messenger has obeyed Allâh ... " (4:79)
"That what the Messenger brings you and leave what he forbids you ... " (59:7)
"Whoever obeys Allâh and the Messenger is with those whom Allâh has blessed." (4:68)
"We did not send any Messenger but for him to be obeyed by the permission of Allâh." (4:63)
He made obeying His Messenger tantamount to obeying Himself, and He placed obedience to Himself alongside obedience to His Messenger. Allâh promises that doing this will result in an abundant reward and threatens a severe punishment for opposing it. He made it obligatory to obey the things that the Prophet commanded and to avoid those he prohibited.
Hadith is integral to the Qur’an, since they are inseparably linked to each other. It is impossible to understand the Qur’an without reference to Hadith. The Qur’an is the message, and the Hadith is the explanation of the message by the Messenger himself. We mention the following points to clarify the issue:
1-The Qur’an makes it abundantly clear that the function of the Messenger is not merely that of a deliveryman who simply delivers the revelation from Allah to us. Rather, he has been entrusted with the most important task of explaining and illustrating the same. This is a point mentioned in a number of verses in the Qur’an (See the Qur’an: 16: 44; 64). Therefore, Hadith explains, clarifies, and removes ambiguities about the Qur’an. Hence, once we reject the Hadith, we may never be able to figure out the whole meaning of the Qur’an.
2-Much of Islam will remain mere abstract concepts without Hadith. We would never know how to pray, fast, pay Zakah, or make pilgrimage without the illustration found in Hadith, for these acts of worship remain as abstract imperatives in the Qur’an.
3-The Qur’an tells us the Prophet (peace and blessings be upon him) has taught not only the Book but also the wisdom (See Qur’an: 96:2; 33:34; 4:113, etc.). As Imam Shafi`i stated, the wisdom mentioned here is the Sunnah of the Prophet (peace and blessings be upon him); so if we were to reject the Hadith, we would be rejecting the Qur’an itself.
4-The Qur’an tells us to obey the Messenger and abide by his decision (See the Qur’an: 4:65; 5:49, etc.). Where we do we find such decisions except in the Hadith?
5-Last but not least, the Qur’an orders the faithful to emulate the role model of the Messenger and reckons it as the only way to gain the pleasure of Allah. It is therefore imperative that we look up to his morals and behavior and emulate them in our lives. We can never do so without studying the Hadith. It is most illuminating in this respect to learn that when `A’ishah (may Allah be pleased with her) was asked to describe the character of the Prophet (peace and blessings be upon him), her definitive answer was, “His character was the Qur’an.” In other words, he personified the best ideals and values of the Qur’an. How could we then neglect the Hadith, which alone can lead us to the precise ways in which the Prophet (peace and blessings be upon him) exemplified the Qur’anic ideals?
Hadith at all times must be evaluated by the well established rules of validation as established by the great scholars. Such firm criteria include the following: If a certain hadith is contrary to the well established principles of the Qur’an or sound reason, it must be rejected.