The Authority of Sunnah


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Sunnah: The Second Source of Islamic Law
The Sunnah of the Holy Prophet Muhammad (
) has been accepted as an important source of Islamic law, next in importance only to the Holy Qur’ân. This status of the sunnah has remained unchallenged and undisputed throughout the centuries. There have been many differences among Muslims in their juristic opinions, but the authority of the Holy Qur’ân and the Sunnah of the Holy Prophet (
) was never denied by any jurist. Leaving aside some scattered individuals who separated themselves from the main stream of the Muslim population, nobody has ever refused to accept the Sunnah of the Holy Prophet (
) as a sacred source of the Islamic law.

The position is still the same, but some non-Muslim orientalists and some of their followers have tried, during the last century to cast some doubts in the authority or the veracity of Hadîth and to develop a suspicious attitude towards the Sunnah. That is why some Muslims who are unable to study Islam through its original sources, when they read such books, often become a bit skeptical in the subject.

The present article intends, therefore, to provide an objective and simple account of the SUNNAH based on the original sources of Islamic learning. The purpose is not to indulge in a hot atmosphere of argumentation which has no bounds or limits, but to narrate the truth as it stands.

Definition of Sunnah

The Sunnah has been defined by the scholars of the science of Hadîth as follows:

“A word spoken, or an act done, or a confirmation given by the Holy Prophet Muhammad (

“Confirmation” in this definition is termed in Arabic as Taqreer. What is meant by this term is like somebody said something, or acted in a particular manner, and his saying or act came to the knowledge of the Holy Prophet (
) and he either confirmed it in express words or remained silent without given any indication of disapproval. Such silence, being an implied approval of the Holy Prophet (
) is also included in the term Sunnah.

As the Sunnah, with all its three kinds (saying, act and confirmation) relates to the Holy Prophet (
), its true status in Islamic law cannot be ascertained without ascertaining the status of the Holy Prophet (
) himself.

The Status of the Holy Prophet (

So, the first pertinent question in the subject is: What status does a prophet occupy when he is sent to the people? Has he no higher a status than that or a message-carrier or a postman who, after delivering the letter, has no concern with it whatsoever? The answer is certainly in the negative. The prophets are not sent merely to deliver the word of Allâh. They are also required to explain the divine Book, to interpret it, to expound it, to demonstrate the ways of its application and to present a practical example of its contents. Their duty is not restricted to reciting the words of the Book, rather they are supposed to teach it and to train people to run their lives in accordance with its requirements. The Holy Qur’ân leaves no doubt concerning this point by saying:

Allâh has surely blessed the believers with His favor when He raised in their midst a Messenger from among themselves, who recites to them His verses and makes them pure and teaches them the Book and the Wisdom, while they were, earlier in open error. (3:164)

He (Allâh) is the One who raised up, among the unlettered, a Messenger from among themselves who recites the verses of Allâh, and makes them pure, and teaches them the Book and the Wisdom. (62:2)

The same functions were attributed to the Holy Prophet (
) in the prayer of Sayyidna Ibrahim (
) when, according to the Holy Qur’ân, he prayed:

Our Lord, raise in their midst a messenger from among themselves who recites to them Your verses and teaches them the Book and the Wisdom and purifies them… (2:129)

These are the terms of reference given to the Holy Prophet (
) which include four distinct functions and the Holy Prophet (
) has been entrusted with all of them:

(1) Recitation of the Verses of Allâh.
(2) Teaching the Book of Allâh.
(3) Teaching the Wisdom.
(4) Making the people pure.

Thus, the Holy Qur’ân leaves no ambiguities in the fact that the Holy Prophet (
) is not supposed to merely recite the verses and then leave it to the people to interpret and apply them in whatever manner they like. Instead, he is sent to “teach” the Book. Then, since teaching the Book is not enough, he is also required to teach “Wisdom” which is something additional to the “Book.” Still, this is not enough, therefore the Holy Prophet (
) has also to “make the people pure,” meaning thereby that the theoretical teaching of the Book and the “Wisdom” must be followed by a practical training to enable the people to apply the Book and the Wisdom in the way Allâh requires them to apply.

These verses of the Holy Qur’ân describe the following functions of the Holy Prophet (

(a) He is the authority in the way the Holy Book [the Qur’ân] has to be recited.
(b) He has the final word in the interpretation of the Book.
(c) He is the only source at which the wisdom based on divine guidance can be learned.
(d) He is entrusted with the practical training of the people to bring his teachings into practice.
These functions of the Holy Prophet (
) can never be carried out unless his teachings, both oral and practical, are held to be authoritative for his followers, and the Muslims who are given under his training are made bound to obey and follow him. The functions (b) and (c), namely, the teaching of the Book and Wisdom require that his sayings should be binding on the followers, while the function (d), the practical training, requires that his acts should be an example for the Ummah, and the Ummah should be bound to follow it.

It is not merely a logical inference from the verses of the Holy Qur’ân quoted above, but it is also mentioned in express terms by the Holy Qur’ân in a large number of verses which give the Muslims a mandatory command to obey and follow him. While doing so, the Holy Qur’ân has used two different terms, namely the “itaa’ah” (to obey) and “ittibaa’” (to follow). The first term refers to the orders and sayings of the Holy Prophet (
) while the second relates to his acts and practice. By ordering the Muslims both to “obey” and to “follow” the Holy Prophet (
), the Holy Qur’ân has given an authority to both his sayings and acts.

read the full online book in the following link:

The Authority of Sunnah - Chapter 1
The Time Limit of the Prophetic Authority

It is sometimes argued by those who hesitate to accept the full authority of the Sunnah, that whenever the Holy Qur’ân has conferred on the Holy Prophet (
) an authority to make laws or to explain and interpret the Book, it meant this authority to be binding on the people of the Prophet’s (
) time only. They were under the direct control and the instant supervision of the Holy Prophet (
) and were addressed by him face to face. Therefore, the Prophetic authority was limited to them only. It cannot be extended to all the generations for all times to come.

This contention leads us to the discovery of the time limits of the Prophetic authority. The question is whether the authority of the Holy Prophet (
) was confined to his own time, or it is an everlasting authority which holds good for all times to come.

The basic question underlying this issue has already been answered in detail; and that is the question of the nature of this authority. It has been established through a number of arguments that the obedience of the Holy Prophet (
) was not enjoined upon the Muslims in his capacity of a ruler. It has been enjoined in his capacity of a prophet. Had it been the authority of a ruler only which the Holy Prophet (
) exercised, it would logically be inferred that the authority is tied up with his rule, and as soon as his administrative rule is over, his authority simultaneously ceases to have effect.

But if the authority is a “Prophetic” authority, and not merely a “ruling authority,” then it is obvious that it shall continue with the continuance of the prophethood, and shall not disappear until the Holy Prophet (
) no longer remains a prophet.

Now, the only question is whether the Holy Prophet (
) was a prophet of a particular nation or a particular time, or his prophethood extended to the whole mankind for all times. Let us seek the answer from the Holy Qur’ân itself. The Holy Qur’ân says:

Say: O mankind! I am the Messenger of Allâh to you all… (7:158)

And We did not send you (O Prophet) except to the entire mankind, bearing good news and warning. (34:28)

And We did not send you save as a mercy unto all the worlds. (21:107)

Blessed be He Who has sent down the Qur’ân on His servant so that he may be a warner to all the worlds. (25:1)

And We have sent you (O Prophet) for mankind as a messenger. And Allâh suffices to be a witness. (4:79)

And the whole mankind is addressed when it is said:

O mankind! The Messenger has come to you with the truth from your Lord, so believe: it is better for you. And if you disbelieve, to Allâh belongs what is in the heavens and in the earth. And Allâh is All-Knowing, All-Wise. (4:170)

The first five verses need no elaboration. They are self-explanatory on the point that the Holy Prophet (
) was sent to the whole mankind and not to a particular people; his prophethood was not limited either in time or in place.
The fifth verse addresses the whole mankind and enjoins upon all of them to believe in the Holy Prophet (
). Nobody can say that the belief of the Holy Prophet (
) was restricted to his own time. It is, according to this verse, incumbent upon all the peoples, of whatever age, to believe in his Prophethood.

It is also mentioned in the Holy Qur’ân that the Holy Prophet (
) is the last Messenger after whom no Prophet is to come:

Muhammad is not the father of any one of your men, but the Messenger of Allâh and the last of the prophets. And Allâh is All-Knowing in respect of everything. (33:40)

This verse made it clear that the Holy Prophet (
) is the last one in the chain of prophets. The earlier prophets were often sent to a particular nation for a particular time, because they were succeeded by other prophets. But no prophet is to come after Muhammad (
). Hence, his prophethood extends to all the nations and all the times. This is what the Holy Prophet (
) himself explained in the following words:

The Israelites were led by the prophets. Whenever a prophet would pass away, another prophet would succeed him. But there is no prophet after me. However, there shall be successors, and shall be in large numbers. (Sahih al-Bukhari Ch. 50 Hadîth 3455)

If the realm of his prophethood would not reach out to the next generations, the people of those generations would be left devoid of the prophetic guidance, while Allâh does not leave any people without prophetic guidance.
In the light of the verses quoted above, there remains no doubt in the fact that the Holy Prophet (
) is a messenger to all the nations for all times to come.

If his prophethood extends to all times, there remains no room for the suggestion that his prophetic authority does no longer hold good and the present day Muslims are not bound to obey and follow him.

There is another point in the subject worth attention:

It is established through a large number of arguments in the first chapter that Allâh Almighty sent no divine book without a messenger. It is also clarified by Allâh that the messengers are sent to teach the Book and to explain it. It is also proved earlier that but for the detailed explanations of the Holy Prophet (
), nobody might know even the way of obligatory prayers.

The question now is whether all these Prophetic explanations were needed only by the Arabs of the Prophetic age. The Arabs of Makkah were more aware of the Arabic language than we are. They were more familiar with the Qur’ânic style. They were physically present at the time of revelation and observed personally all the surrounding circumstances in which the Holy Book was revealed. They received the verses of the Holy Qur’ân from the mouth of the Holy Prophet (
) and were fully aware of all the factors which help in the correct understanding of the text. Still, they needed the explanations of the Holy Prophet (
) which were binding on them.

Then, how can a man of ordinary perception presume that the people of this age, who lack all these advantages, do not need the explanations of a prophet? We have neither that command on the Arabic language as they had, nor are we so familiar with the Qur’ânic style as they were, nor have we seen the circumstances in which the Holy Qur’ân was revealed, as they have seen. If they needed the guidance of the Holy Prophet (
) in interpreting the Holy Qur’ân, we should certainly need it all the more.

If the authority of the Holy Qur’ân has no time-limit, if the text of the Qur’ân is binding on all generations for all times to come, then the authority of the Messenger, which is included in the very Qur’ân without being limited to any time bond, shall remain as effective as the Holy Qur’ân itself. While ordaining for the “obedience of the messenger,” the Holy Qur’ân addressed not only the Arabs of Makkah or Madînah. It has addressed all the believers when it was said:

O those who believe, obey Allâh and obey the Messenger and those in authority among you. (4:59)​

If the “obedience of Allâh” has always been combined with the “obedience of the Messenger” as we have seen earlier, there is no room for separating any one from the other. If one is meant for all times, the other cannot be meant for a particular period. The Holy Qur’ân at another place has also warned against such separation between Allâh and His Messenger:

Those who disbelieve in Allâh and His Messengers, and desire to make separation between Allâh and His Messengers and say, “We believe in some and disbelieve in some,” desiring to adopt a way in between this and that—those are the unbelievers in truth; and We have prepared for the disbelievers a humiliating punishment. (4:150-151)
Therefore, the submission to the authority of the Holy Prophet (
) is a basic ingredient of having belief in his prophethood, which can never be separated from him. Thus, to accept the prophetic authority in the early days of Islâm, and to deny it in the later days, is so fallacious a proposition that cannot find support from any source of Islâmic learning, nor can it be accepted on any touchstone of logic and reason.
The Authority of the Sunnah: Its Historical Aspect

Faced with the overwhelming arguments in favour of the authority of sunnah, some people resort to another way of suspecting its credibility, that is, to suspect its historical authenticity.

According to them, the sunnah of the Holy Prophet (
) though having a binding authority for all times to come, has not been preserved in a trustworthy manner. Unlike the Holy Qur’ân, they say, there is no single book containing reliable reports about the sunnah. There are too many works having a large number of traditions sometimes conflicting each other. And these books, too, were compiled in the third century of Hijrah. So, we cannot place our trust in the reports which have not even been reduced to writing during the first three centuries.

This argument is based on a number of misstatements and misconceptions. As we shall see in this chapter, inshâ-Allâh, it is totally wrong to claim that the traditions of the sunnah have been compiled in the third century. But, before approaching this historical aspect of the sunnah, let us examine the argument in its logical perspective.

This argument accepts that the Holy Prophet (
) has a prophetic authority for all times to come, and that his obedience is mandatory for all Muslims of whatever age, but in the same breath it claims that the reports of the sunnah being unreliable, we cannot carry out this obedience. Does it not logically conclude that Allâh has enjoined upon us to obey the Messenger, but did not make this obedience practicable. The question is whether Allâh Almighty may give us a positive command to do something which is beyond our ability and means. The answer is certainly “no.” The Holy Qur’ân itself says,
Allâh does not task anybody except to his ability.​

It cannot be envisaged that Allâh will bind all the people with something which does not exist or cannot be ascertained. Accepting that Allâh has enjoined upon us to follow the sunnah of the Holy Prophet (
), it certainly implies that the sunnah is not undiscoverable. If Allâh has made it obligatory to follow the sunnah, He has certainly preserved it for us, in a reliable form.
The following aspect also merits consideration. Allâh Almighty has given us a promise in the Holy Qur’ân:

Indeed We have revealed the Zikr (ie. the Qur’ân) and surely We will preserve it. (15:9)

In this verse, Allâh Almighty has assured the preservation of the Holy Qur’ân. This implies that the Qur’ân will remain uninterpolated and that it shall always be transferred from one generation to the other in its real and original form, undistorted by any foreign element. The question now is whether this divine protection is restricted only to the words of the Holy Qur’ân or does it extend to its real meanings as well. If the prophetic explanation is necessary to understand the Holy Qur’ân correctly, as proved in the first chapter, then the preservation of the Qur’ânic words alone cannot serve the purpose unless the prophetic explanations are also preserved. As quoted earlier, the Holy Book says,

We have revealed to you the Zikr (Qur’ân) so that you may explain to the people what has been sent down for them.​

The word “Zikr” has been used here for the Holy Qur’ân as has been used in the verse 15:9 and it has been made clear that the people can only benefit from its guidance when they are led by the explanations of the Holy Prophet (

Again, the words “for the people” indicate (especially in the original Arabic context), that the Holy Prophet’s (
) explanation is always needed by “everyone.”

Now, if everyone, in every age is in need of the prophetic explanation, without which they cannot fully benefit from the Holy Book, how would it be useful for them to preserve the Qur’ânic text and leave its prophetic explanation at the mercy of distorters, extending to it no type of protection whatsoever.

Therefore, once the necessity of the prophetic explanations of the Holy Qur’ân is accepted, it will be self-contradictory to claim that these explanations are unavailable today. It will amount to negating the divine wisdom, because it is in no way a wise policy to establish the necessity of the sunnah on the one hand and to make its discovery impossible on the other. Such a policy cannot be attributed to Allâh, the All-Mighty, the All-Wise.

This deductive argument is, in my view, sufficient to establish that comprehending the sunnah of the Holy Prophet (
), which is necessary for the correct understanding of the divine guidance, shall as a whole remain available in a reliable manner forever. All objections raised against the authenticity of the sunnah as a whole can be repudiated on this score alone. But in order to study the actual facts, we are giving here a brief account of the measures taken by the ummah to preserve the sunnah of the Holy Prophet (
). It is a brief and introductive study of the subject, for which the comprehensive and voluminous books are available in Arabic and other languages. The brief account we intend to give here is not comprehensive. The only purpose is to highlight some basic facts which, if studied objectively, are well enough to support the deductive inference about the authenticity of the sunnah.
The Preservation of Sunnah

It is totally wrong to say that the sunnah of the Holy Prophet (
) was compiled for the first time in the third century. In fact, the compilation had begun in the very days of the Holy Prophet (
) as we shall see later, though the compilations in a written form were not the sole measures adopted for the preservation of the sunnah. There were many other reliable sources of preservation also. In order to understand the point correctly we will have to know the different kinds of the sunnah of the Holy Prophet (

Three Kinds of Ahâdîth

An individual tradition which narrates a “sunnah” of the Holy Prophet (
) is termed in the relevant sciences as “hadîth” (pl. ahâdîth). The ahâdîth, with regard to the frequency of their sources, are divided into three major kinds:

(1) Mutawâtir: It is a hadîth narrated in each era, from the days of the Holy Prophet (
) up to this day by such a large number of narrators that it is impossible to reasonably accept that all of them have colluded to tell a lie.
This kind is further classified into two sub-divisions:

(a) Mutawâtir in words: It is a hadîth whose words are narrated by such a large number as is required for a mutawâtir, in a manner that all the narrators are unanimous in reporting it with the same words without any substantial discrepancy.

(b) Mutawâtir in meaning: It is a mutawâtir hadîth which is not reported by the narrators in the same words. The words of the narrators are different. Sometimes even the reported events are not the same. But all the narrators are unanimous in reporting a basic concept which is common in all the reports. This common concept is also ranked as a mutawâtir concept.

For example, there is a saying of the Holy Prophet (

Whoever intentionally attributes a lie against me, should prepare his seat in the Fire.

This is a mutawâtir hadîth of the first kind, because it has a minimum of seventy-four narrators. In other words, seventy-four companions of the Holy Prophet (
) have reported this hadîth at different occasions, all with the same words.

The number of those who received this hadîth from these companions is many times greater, because each of the seventy-four companions has conveyed it to a number of his pupils. Thus, the total number of the narrators of this hadîth has been increasing in each successive generation, and has never been less than seventy-four. All these narrators, who are now hundreds in number, report it in the same words without even a minor change. This hadîth is, therefore, mutawâtir by words, because it cannot be imagined reasonably that such a large number of people have colluded to coin a fallacious sentence in order to attribute it to the Holy Prophet (

On the other hand, it is also reported by such a large number of narrators that the Holy Prophet (
) has enjoined us to perform two rak’ât in Fajr, four rak’ât in Zuhr, ‘Asr and ‘Isha, and three rak’ât in the Maghrib prayer, yet the narrations of all the reporters who reported the number of rak’ât are not in the same words. Their words are different. Even the events reported by them are different. But the common feature of all the reports is the same. This common feature, namely, the exact number of rak’ât, is said to be mutawâtir in meaning.

(2) The second kind of hadîth is Mashhoor. This term is defined by the scholars of hadîth as follows:

“A hadîth which is not mutawâtir, but its narrators are not less than three in any generation.” [Tadreeb-ur-Râwi by Suyuti]
The same term is also used by the scholars of fiqh, but their definition is slightly different. They say,

“A mashhoor hadîth is one which was not mutawâtir in the generation of the Holy Companions, but became mutawâtir immediately after them.” [Usool of Sarkhasi]

The mashhoor hadîth according to each definition falls in the second category following the mutawâtir.

(3) Khabar-ul-Wâhid. It is a hadîth whose narrators are less than three in any given generation.

Let us now examine each kind separately.

The Authenticity of the First Two Kinds

As for the mutawâtir, nobody can question its authenticity. The fact narrated by a mutawâtir chain is always accepted as an absolute truth even if pertaining to our daily life. Any statement based on a mutawâtir narration must be accepted by everyone without any hesitation. I have never seen the city of Moscow, but the fact that Moscow is a large city and is the capital of U.S.S.R. is an absolute truth which cannot be denied. This fact is proved, to me, by a large number of narrators who have seen the city. This is a continuously narrated, or a mutawâtir, fact which cannot be denied or questioned.

I have not seen the events of the First and the Second World War. But the fact that these two wars occurred stands proved without a shadow of doubt on the basis of the mutawâtir reports about them. Nobody with a sound sense can claim that all those who reported the occurrence of these two wars have colluded to coin a fallacious report and that no war took place at all. This strong belief in the factum of war is based on the mutawâtir reports of the event.

In the same way the mutawâtir reports about the sunnah of the Holy Prophet (
) are to be held as absolutely true without any iota of doubt in their authenticity. The authenticity of the Holy Qur’ân being the same Book as that revealed to the Holy Prophet (
) is of the same nature. Thus, the mutawâtir ahâdîth, whether they be mutawâtir in words or in meaning, are as authentic as the Holy Qur’ân, and there is no difference between the two in as far as the reliability of their source of narration is concerned.
Although the ahâdîth falling under the first category of the mutawâtir, ie. the mutawâtir in words, are very few in number, yet the ahâdîth relating to the second kind, namely the mutawâtir in meaning, are available in large numbers. Thus, a very sizeable portion of the sunnah of the Holy Prophet (
) falls in this kind of mutawâtir, the authenticity of which cannot be doubted in any manner.

As for the second kind, ie. the mashhoor, its standard of authenticity is lower than that of the mutawâtir; yet, it is sufficient to provide satisfaction about the correctness of the narration because its narrators have been more than three trustworthy persons in every generation.

The third kind is khabar-ul-wâhid. The authenticity of this kind depends on the veracity of its narrators. If the narrator is trustworthy in all respects, the report given by him can be accepted, but if the single reporter is believed to be doubtful, the entire report subsequently remains doubtful. This principle is followed in every sphere of life. Why should it not be applied to the reports about the sunnah of the Holy Prophet (
)? Rather, in the case of ahâdîth, this principle is most applicable, because the reporters of ahâdîth were fully cognizant of the delicate nature of what they narrate. It was not simple news of an ordinary event having no legal or religious effect. It was the narration of a fact which has a far-reaching effect on the lives of millions of people. The reporters of ahâdîth knew well that it is not a play to ascribe a word or act to the Holy Prophet (
). Any deliberate error in this narration, or any negligence in this respect would lead them to the wrath of Allâh and render them liable to be punished in hell. Every reporter of hadîth was aware of the following well-known mutawâtir hadîth:

Whoever intentionally attributes a lie against me, should prepare his seat in the Fire.​

This hadîth had created such a strong sense of responsibility in the hearts of the narrators of ahâdîth that while reporting anything about the Holy Prophet (
) they often turned pale out of fear, lest some error should creep into their narration.

This was the basic reason for which the responsible narrators of ahâdîth showed the maximum precaution in preserving and reporting a hadîth. This standard of precaution cannot be found in any other reports of historical events. So, the principle that the veracity of a report depends on the nature of its reporter is far more validly applicable to the reports of ahâdîth than it is applicable to the general reports of ordinary nature.

Let us now examine the various ways adopted by the ummah to preserve the ahâdîth in their original form.

Different Ways of Ahâdîth Preservation

As we shall later see, the companions of the Holy Prophet (
) reduced a large number of ahâdîth in writing. Yet, writing was not the sole means of their preservation. There were many other ways.

1. Memorization
First of all, the companions of the Holy Prophet (
) used to learn ahâdîth by heart. The Holy Prophet (
) has said:

May Allâh bestow vigor to a person who hears my saying and learns it by heart and then conveys it to others exactly as he hears it.

The companions of the Holy Prophet (
) were eager to follow this hadîth and used to devote considerable time for committing ahâdîth to their memories. A large number of them left their homes and began to live in the Mosque of the Holy Prophet (
) so that they may hear the ahâdîth directly from the mouth of the Holy Prophet (
). They spent all their time exclusively in securing the ahâdîth in their hearts. They are called Ashâb as-Suffah.

The Arabs had such strong memories that they would easily memorize hundreds of verses of their poetry. Nearly all of them knew by heart detailed pedigrees of not only themselves, but also of their horses and camels. Even their children had enough knowledge of the pedigrees of different tribes. Hammâd is a famous narrator of Arab poetry. It is reported that he knew by heart one hundred long poems for each letter of the alphabet, meaning thereby that he knew three thousand and thirty-eight long poems [al-A’lam by Zrikli 2:131].

The Arabs were so proud of their memory power that they placed more of their confidence on it than on writing. Some poets deemed it a blemish to preserve their poetry in writing. They believed that writings on papers can be tampered with, while the memory cannot be distorted by anyone. If any poets have written some of their poems, they did not like to disclose this fact, because it would be indicative of a defect in their memory [See al-Aghani 61:611].

The companions of the Holy Prophet (
) utilized this memory for preserving ahâdîth which they deemed to be the only source of guidance after the Holy Qur’ân. It is obvious that their enthusiasm towards the preservation of ahâdîth far exceeded their zeal for preserving their poetry and literature. They therefore used their memory in respect of ahâdîth with more vigor and more precaution.

Sayyidunâ Abû Hurairah (
), the famous companion of the Holy Prophet (
), who has reported 5,374 ahâdîth, says:

I have divided my night into three parts: In one third of the night I perform prayer, in one third I sleep and in one third I memorize the ahâdîth of the Holy Prophet (
). [Sunan ad-Dârimi]

read the full, brief acount of how the Sunnah has been preserved, on the follwing link:

The Authority of Sunnah - Chapter 3