As false attributions to the Prophet ﷺ multiplied in the late seventh century, how were those Muslims who sought to preserve his authentic legacy to distinguish between true and forged hadiths? While the ahl al-raʾy scholars in Iraqi cities like Kufa attempted to rise above the flood of forged hadiths by depending on the Qur’an, well-established hadiths, and their own legal reasoning, the school that would give birth to the Sunni tradition, the ahl al-ḥadīth, evolved the three-tiered approach to determining the authenticity of a hadith. The first tier was demanding a source (isnād) for the report, the second was evaluating the reliability of that source, and the third was seeking corroboration for the hadith.
The processes of this three-tiered critical method did not emerge fully until the mid eighth century with critics like Mālik (d. 179/795) and Shuʿbah ibn al-Ḥajjāj (d. 160/776). Certainly, Successors like al-Zuhrī (d. 124/742) and even Companions had examined critically material they heard attributed to the Prophet ﷺ. Moreover, the critical opinions of Successors would inform later hadith critics. A formalized system of requiring isnāds and investigating them according to agreed conventions and through a set of technical terms, however, did not appear until the time of Mālik.
Step one: The isnād
, or ‘support,’ was the essential building-block of the hadith critical method. So essential would the isnād
be to the Sunni science of hadith criticism that it became the veritable symbol of the ‘cult of authenticity’ that is Sunni Islam. One of the most oft-repeated slogans among hadith critics comes from the famous scholar Ibn al-Mubārak (d. 181/797), who said, “The isnād
is part of religion; if not for the isnād
, whoever wanted could say whatever they wanted. But if you
ask them, ‘Who told you this?’ they cannot reply.” Al-Shāfiʿī provided a similarly famous declaration, “The person who seeks knowledge without an isnād
, not asking “Where is this from?,” indeed, he is like a person gathering wood at night. He carries on his back a bundle of wood when there may be a viper in it that could bite him.” Sunnis thus understood the isnād
as the prime means of defending the true teachings of the Prophet ﷺ against heretics as well as protection from subtle deviations that might slip into Muslims’ beliefs and practice.
The origins of the isnād were as commonsense as its function, beginning with the rise of hadith forgery. As the Successor Muhammad ibn Sīrīn (d. 110/729), a leading student of the Companion Anas ibn Mālik, explained:
In the early period no one would ask about the isnād. But when the Strife [most probably the Second Civil War, 680–692 CE] began, they would say “Name for us your sources” so that the People of the Sunnah (ahl al-sunnah) could be identified and their hadiths accepted, and the People of Heresy (ahl al-bidʿah) could be identified and their hadiths ignored.
In the milieu of the early Islamic period, simply demanding an isnād
for reports attributed to the Prophet ﷺ was an excellent first line of defense against inauthentic material entering Muslim discourse. We can imagine the newly Muslim inhabitants of Kufa, still clinging to Christian or Zoroastrian lore, or even Bedouins eager to insinuate tribal Arab values into Islam, ascribing a saying to the Prophet as evidence for their ideas. If they provided no isnād
at all, the reports would not enter the musnad
collections of scholars like Abū Dāwūd al-Ṭayālisī (d. 204/820). The formative critic Shuʿba is quoted as saying, “All religious knowledge (ʿilm
) which does not feature ‘he narrated to me’ or ‘he reported to me’ [the components of the isnād
] is just vinegar and sprouts.”
Step two: Rating transmitters and establishing contiguous transmission
On their own, however, isnāds could not deter a determined forger. As we saw with the hadiths on human reason, an isnād could be made up or inauthentic material could simply be equipped with an isnād and then circulated. Moreover, merely requiring someone to provide a source for a hadith they cited did not tell you if that source was reliable. The second tier of criticism thus involved identifying the individuals who constituted isnāds, evaluating their reliability, and then determining if there were any risks that someone unreliable might also have played some part in transmitting the report.
1) Transmitter evaluation
A hadith transmitter was evaluated according to two criteria. First, his or her character, correct belief, and level of piety were scrutinized in order to determine if he or she was ‘upright’ (ʿadl). Second, and much more importantly, the transmitter’s corpus of reports and narration practices were evaluated to decide if he or she was ‘accurate’ (ḍābit).
Hadith transmitter criticism (known as al-jarḥ wa-al-taʿdīl
, ‘impugning and approving’) and isnād
evaluation began in full with the first generation of renowned hadith critics, that of Shuʿbah ibn al-Ḥajjāj, Mālik ibn Anas, Sufyān al-Thawrī, al-Layth ibn Saʿd, and Sufyān ibn ʿUyaynah, who flourished in the mid to late eighth century in the cities of Basra, Kufa, Fustat (modern-day Cairo), Mecca, and Medina (see Figure 2). These scholars began the process of collecting people’s hadith narrations and examining both their bodies of material and their characters to determine if the material they purveyed could be trusted. Mālik is the first scholar known to have used technical terms such as ‘thiqah
’ (reliable) to describe these narrators, while Shuʿba’s evaluations did not utilize any specialized vocabulary.
The evaluations of this first great generation were studied and added to by their students, especially the two great Basran critics ʿAbd al-Raḥmān ibn Mahdī (d. 198/814) and Yahyá ibn Saʿīd al-Qaṭṭān (d. 198/813). The later analyst Shams al-Dīn al-Dhahabī notes that “whoever they both criticize, by God, rarely do you find that criticism refuted [by others], and whoever they both agree on as trustworthy, he is accepted as proof.”
The critical methods and opinions of Ibn Mahdī and al-Qaṭṭān passed on to their three most respected students, who can be seen as the beginning of the heyday of Sunni hadith criticism: Ibn Ḥanbal (d. 241/855) and his friend Yahyá ibn Maʿīn (d. 233/848) in Baghdad and ʿAlī ibn al-Madīnī in Basra (d. 234/849). Their students refined hadith criticism into its most exact and lasting form: the ‘Two Shaykhs’ al-Bukhārī and Muslim, the two senior critics of Rayy (modern Tehran), Abū Zurʿah al-Rāzī (d. 264/878) and his friend Abū Ḥātim al-Rāzī (d. 277/890), as well as influential younger critics of that generation such as al-Nasāʾī (d. 303/916).
The 900s saw several generations of critics who reviewed and reassessed the judgments of these earlier scholars and also continued to evaluate those involved in the ongoing transmission of hadiths: Ibn Abī Ḥātim al-Rāzī (d. 327/938), Ibn ʿAdī (d. 365/975-6), Ibn Ḥibbān al-Bustī (d. 354/965), Abū al-Ḥasan al-Dāraquṭnī (d. 385/995), and al-Hākim al-Naysābūrī (d. 405/1014).
Although the apex and most active period of hadith transmitter criticism is usually considered to be the eighth to tenth centuries, subsequent generations of critics contributed to this science as well. Hadiths were still transmitted with full isnāds into the early 1200s, so it was possible until that time for previously unrated hadiths to be in circulation among transmitters. Master hadith scholars like al-Khaṭīb al-Baghdādī (d. 463/1071) and Ibn ʿAsākir (d. 571/1176) therefore continued to rate transmitters living in their times. Furthermore, they synthesized, reconciled, and reexamined existing opinions on earlier transmitters.
This reconsideration of earlier transmitters’ standing has, in fact, never really ended. If we look at al-Dhahabī’s list of the expert critics whose opinions should be heeded, we find that it continues until al-Dhahabī ’s own time in the 1300s. One of the most commanding critics in the Sunni hadith tradition, ‘the Hadith Master (al-ḥāfiẓ)’ Ibn Ḥajar al-ʿAsqalānī, died in 852/1449. Hadith transmitter criticism has continued until the modern day. This is possible because, as we shall see, determining if someone was reliable or not had little to do with any personal experience with their character, its flaws, or fine qualities. Ultimately, it was the analysis of the body of their transmissions for corroboration that determined their accuracy (ḍabt) and thus their station.
How would a hadith critic such as Shuʿbah, al-Bukhārī, or Ibn ʿAdī actually evaluate a transmitter? First, it was essential to know who this transmitter was. If one was presented with a hadith transmitted from ‘someone,’ ‘Aḥmad,’ or ‘a group of people in Medina,’ how could one evaluate the strength of its isnād? By the mid 800s it had become accepted convention among hadith critics that a person needed two well-known transmitters to identify him sufficiently, prove that he existed, and narrate hadiths from him in order to qualify for rating. Otherwise, the transmitter would be dismissed as ‘unknown’ (majhūl) and the report automatically considered unreliable.
Second, the critic would collect all the reports that the transmitter had narrated from various teachers and then analyze them for corroboration, a process known as ‘consideration' (iʿtibār). It was here that the musnad genre of hadith collection would be very useful, since they were organized not by subject matter but by narrators in the isnāds. But ultimately a critic would have to rely on a robust memory in order to recall all the different isnāds in which the transmitter in question played some part. For every hadith that the transmitter narrated from a certain teacher, the critic asks, “Did this teacher’s other students narrate this report too?” If the critic finds that, for all the teachers that the transmitter narrates from, his fellow students corroborated him for a very high percentage of his hadiths, then he is considered to be reliable in his transmissions. When asked what kind of transmitters should be abandoned as unreliable, Shuʿbah explained:
Someone who narrates excessively from well-known transmitters what these well-known transmitters do not recognize, his hadiths are cast aside. And if he makes a lot of mistakes, his hadiths are cast aside. And if he is accused of forgery (kādhib), his hadiths are cast aside. And if he narrates a hadith that is agreed upon as an error, and he does not hold himself accountable for that and reject the report, his hadiths are cast aside.
Muslim ibn al-Ḥajjāj describes the telltale signs of a weak hadith transmitter as someone who, “when his narrations are compared with those of people known for preservation [of hadith] and uprightness of character, his narrations do not concur with their narrations, or do so only rarely. If the majority of his hadiths are like that then he is rejected and not used in hadith.”
Early hadith critics understood very well that no one transmitter was immune from error. Below the level of master transmitters, Ibn Mahdī described a lesser type of narrator “who makes errors, but most of his hadiths are ṣaḥīḥ
. This kind of person’s hadiths should not be abandoned, for if they were, all the people’s hadiths would disappear.”
Finally, the critic would examine the transmitter’s character, religious beliefs, and piety in order to determine his ‘uprightness’ (ʿadālah). Although later legal theorists would establish very formal requirements for someone to be declared ‘upright,’ such as the requirement widely accepted by Sunnis after the 1200s that the transmitter be “Muslim, of age, of sound mind, free of sinful behavior and defects in honor,” early hadith critics were actually very flexible with determining uprightness.
This is most evident in the issue of transmitters who espoused beliefs that Sunnis considered heretical, such as Shiism, belonging to the Kharijite sect, or a belief in free will (qadar). Although al-Shāfiʿī had declared that one could accept hadiths from transmitters regardless of their sectarian affiliations as long as they did not belong to certain Shiite sects that allowed lying, by the mid 900s scholars like Ibn Ḥibbān had declared a consensus among Sunni hadith critics that one could accept hadiths from any heretical transmitter provided he was not an extremist and did not actively try to convert others to his beliefs. In theory, this meant that one could accept hadiths from Shiite transmitters as long as they did not engage in virulently anti-Sunni practices such as cursing Abū Bakr or ʿUmar or transmit hadiths that seemed to preach the Shiite message.
In truth, however, early hadith critics did not follow these strictures. As the eighteenth-century Yemeni hadith analyst Ibn al-Amīr al-Ṣanʿānī (d. 1768) observed, later theorists had set up principles that did not apply to the realities of early hadith criticism. Al-Bukhārī, the most revered of all hadith critics, narrated two hadiths in his famous Ṣaḥīḥ through the extreme Kharijite ʿImrān ibn Ḥiṭṭān. In his Sahīh, Muslim narrated the hadith that “Only a believer loves ʿAlī, and only a hypocrite hates him” through the known Shiite transmitter ʿAdī ibn Thābit. As we can see, the two uncontested masters of Sunni hadith criticism could narrate hadiths that they considered authentic through extremists and heretics who proselytized for their cause.
The explanation for this lies in the priorities of the early hadith critics. Simply put, if a transmitter consistently and accurately passed on hadiths he had heard from the previous generation, hadith critics had little interest in his beliefs or practice. Ibn Maʿīn described the Shiite transmitter ʿAbd al- Raḥmān ibn Ṣāliḥ as “trustworthy, sincere, and Shiite, but who would rather fall from the sky than misrepresent half a word.”
One prominent early hadith transmitter, Ismāʿīl ibn ʿUlayyah (d. 193/809), became so shamefully intoxicated on one occasion that he had to be carried home on a donkey. Yet he was a reliable transmitter, so his hadiths were accepted.
Although later theorists of the hadith tradition would talk of the two pillars of reliability as ‘uprightness (ʿadālah
) and accuracy (ḍabt
),’ al-Sanʿānī rightly pointed out that one should reorder them ‘accuracy and uprightness,’ since the former greatly outweighed the latter.
Ultimately, Sunnis could not escape their dependency on the role of ‘non-Sunnis’ in hadith transmission. The early critic Ibn Saʿd (d. 230/845) notes how one Khālid al-Qaṭwānī was a staunch Shiite but that hadith scholars “wrote down his hadiths out of necessity.”
Without such ‘heretics,’ critics knew that few hadiths would ever have been transmitted.
Guaranteeing the transmitter’s ‘uprightness’ (ʿadālah
), however, did have an important function. Regardless of a transmitter’s accuracy, if they were known to have intentionally misrepresented the Prophet ﷺ or forged a hadith, then they could not be trusted. Sulaymān ibn Dāwūd al-Shādhakūnī (d. 234/848-9), for example, was considered to have the most prodigious memory of hadiths in his time and one of the biggest hadith corpora. Yet he was known to have lied about hadiths and altered them to fit certain situations, so he was excluded from transmission. Al-Shādhakūnī was so untrustworthy that when he awed a gathering by claiming that he knew a hadith from Rayy that Abū Zurʿah al-Rāzī did not know, people believed that he had just made it up on the spot to impress them.
Although in the eighth and ninth centuries each hadith critic used slightly different and sometimes shifting terms to describe a transmitter’s level of reliability, by the early tenth century a conventional jargon had emerged. Ibn Abī Ḥātim al-Rāzī (d. 327/938) lists the levels as:
- ‘Reliable’ (thiqah, mutqin, thabt) transmitter’s hadiths can be used as proof in legal scholarship with no hesitation
- ‘Sincere’ (sadūq, lā baʾs bihi) transmitter’s hadiths are recorded and can be taken as proof if bolstered or corroborated
- ‘Venerable’ (shaykh) transmitter’s hadiths are used for identifying corroboration depending on strength
- ‘Righteous’ (ṣāliḥ) transmitter’s hadiths are used for identifying corroboration depending on strength
- ‘Lenient on hadith’ (layyin al-ḥadīth) transmitter’s hadiths can be used for identifying corroboration
- ‘Not strong’ (laysa bi-qawī) transmitter’s hadiths can still be used for identifying corroboration
- ‘Weak’ (daʿīf) transmitter’s hadiths can be used to corroborate but not on their own
- 'Liar, abandoned’ (matrūk al-ḥadīth, dhāhib al-ḥadīth, kadhdhāb) transmitter’s hadiths are not used at all.47
Books of transmitter criticism
Hadith transmitter criticism often took place in discussion sessions among critics or with their students, but its results were set down by master critics in dictionaries of transmitter evaluation (kutub al-rijāl). Early works include the Ṭabaqāt al-kubrá (The Great Book of Generations) of Ibn Saʿd (d. 230/845), the Aḥwāl al-rijāl (Conditions of the Transmitters) of al-Jūzajānī (d. 259/873), the massive ‘Great History (al-Tārīkh al-kabīr)’ of al-Bukhārī, and the Jarḥ wa-al-taʿdīl of Ibn Abī Ḥātim al-Rāzī. Some books focused specifically on discussing transmitters whom the author felt were reliable; these included al-ʿIjlī’s (d. 261/875) Tārīkh al-thiqāt and Ibn Ḥibbān’s Kitāb al-thiqāt. Voluminous books were devoted to listing and discussing weak transmitters as well. The most important are the Kitāb al-duʿafāʾ al-kabīr of al-Bukhārī (now lost), the Kāmil fī duʿafāʾ al-rijāl of Ibn ʿAdī and Ibn Hibbān’s Kitāb al-majrūḥīn. Such works presented critics’ opinions of a transmitter along with a selection of the unacceptable narrations that they transmitted. Because they consistently evaluated the reliability of personalities they mention, local histories like al-Khaṭīb’s History of Baghdad are also works of transmitter criticism.
In the period of consolidation and analysis from the 1300s to the 1600s, later critics amalgamated and digested these earlier works of hadith criticism. ʿAbd al-Ghanī al-Maqdisī (d. 600/1203) wrote his al-Kamāl fī maʿrifat asmāʾ al-rijāl (The Perfection in Knowing the Names of Transmitters), presenting earlier descriptions and evaluations of all the transmitters in the Six Books. Jamāl al-Dīn al-Mizzī (d. 742/1341) added to this work and further analyzed the ratings of the transmitters within the Six Books in his Tahdhīb al-kamāl (The Refinement of Perfection), published today in thirty-five volumes. Ibn Ḥajar al-ʿAsqalānī produced an abridgment of this work with his own comments entitled Tahdhīb al-tahdhīb (The Refinement of the Refinement). Scholars like the Egyptian Ibn al-Mulaqqin (d. 804/1401) added the transmitters found in other hadith collections such as the Musnads of Ibn Ḥanbal and al-Shāfiʿī as well as the Ṣaḥīḥ of Ibn Khuzaymah and the Mustadrak of al-Ḥākim to expanded versions of al-Mizzī’s book. The Ḥanafī scholar of Cairo, Badr al-Dīn al-ʿAynī (d. 855/1451), devoted a rijāl work to the transmitters in al-Ṭaḥāwī’s collections.
Other later analysts focused on the subject of weak transmitters. Shams al-Dīn al-Dhahabī wrote his masterful Mīzān al-iʿtidāl fī naqd al-rijāl (The Fair Scale for Criticizing Transmitters), collecting all the information on any transmitter impugned by earlier figures. Ibn Ḥajar added his own comments in a revision of this work, Lisān al-mīzān (The Pointer of the Scale).
As we saw in the last chapter, the isnāds to hadith books could affect the reliability of hadiths in them, especially during the ninth and tenth centuries. Scholars like Ibn Nuqṭah of Baghdad (d. 629/1231) therefore wrote books of transmitter criticism addressing the people who conveyed books from their authors. Ibn Nuqṭah’s al-Taqyīd fī maʿrifat ruwāt al-sunan wa-al-masānīd and Abū ʿAlāʾ al-Fāsī’s (d. 1770) addendum to that book are examples of this genre.
Reconciling disagreements among critics
With the plethora of transmitter critics from the eighth century on, how was a later critic or analyst supposed to know whose opinion to take on the reliability of a narrator or a hadith? Ibn Isḥāq (d. 150/767), for example, the author of the famous biography of the Prophet ﷺ, was a very controversial figure. Mālik, Ibn al-Qaṭṭān, Ibn Ḥanbal, and others considered him highly unreliable because he accepted hadiths from questionable narrators as well as Christians and Jews. But Shuʿbah felt he was impeccably reliable, ʿAlī ibn al-Madīnī named him one of the pivots of hadith transmission in his age, and all the Six Books relied on him as a narrator (though the Ṣaḥīḥayn of al-Bukhārī and Muslim only use him for rare backup narrations). Certainly, this created a great potential for disagreement over the reliability of transmitters and, hence, of hadiths themselves.
To a certain extent, such disagreement was the inevitable result of the complicated careers of transmitters and the contrasting critical thresholds of the many individual analysts examining them and their reports. One critic could change his mind about a transmitter, as al-Bukhārī did when he reduced Muhammad ibn Ḥumayd al-Rāzī’s rating from ‘good’ to ‘weak.’ As the hadith scholar al-Ismāʿīlī (d. 371/981) noted, critics often rated transmitters in relation to certain of their teachers. So a critic might describe a transmitter positively in one place and negatively in another.
In general, however, later analysts erred on the side of caution and operated on the principle that ‘criticism supersedes approval provided that the reason for the criticism is provided.’ There were limits to this, however. Scholars who had personal vendettas against one another—Mālik’s criticism of Ibn Isḥāq was the result of a well-documented personal feud between them—were not accepted as fair critics of one another.
Later analysts were often aware of such issues and took earlier critics’ idiosyncrasies and personal leanings into consideration. Al-Jūzajānī was known to have a vehement dislike for Shiism, so any rejection by him of a transmitter as ‘a heretical Shiite’ was probably an overstatement. If he approved of a transmitter, however, it meant that he was certainly free of any Shiite tendencies. Abū Ḥātim al-Rāzī was well known as a very stringent critic—even the seminal legal and hadith scholar al-Shāfiʿī had only merited a ‘sincere (ṣadūq
)’ rating with him. Ibn Maʿīn was very harsh—once calling a narrator who criticized a Companion a… person who had improper relations with his own mother—so his approval carried great weight.
Ibn ʿAdī was generally very objective. He would limit his evaluations to strict examinations of transmitters’ hadiths for corroboration or its absence. As a result, he would often overturn the disapproval of an earlier critic with a comment such as “I have not found uncorroborated reports among his hadiths.”
The standing of the Companions
The Companions of the Prophet ﷺ achieved a unique place in the worldview of Sunni hadith critics. Although some early historians and transmitters like al-Wāqidī (d. 207/822–3) only considered those who reached adulthood during the lifetime of the Prophet to be Companions, the definition that became accepted by Sunnis was much less strict.
As al-Bukhārī notes in his Ṣaḥīḥ
, a Companion is anyone who saw the Prophet, even for a moment, while a believer and who then died as a Muslim.
This had tremendous consequences for hadith transmission, for by 900 CE Sunnis considered that all the Companions of the Prophet were automatically ‘upright (ʿadl
).’ This belief was based on Qur’anic verses such as “You are the best community brought out for humanity” (kuntum khayr ummah ukhrijat lil-nās
) (Qur’an 3:110) and Prophetic hadiths such as “The best of generations is the one in which I was sent, then that which follows, then that which follows.”
then, the first generation of hadith transmitters was beyond criticism. In fact, the famous ninth-century hadith critic Abū Zurʿah al-Rāzī stated that anyone who criticized a Companion was a heretic.
Later analysts would refine this understanding of the Companions’ uprightness. As Ibn Taymiyyah (d. 728/1328) explained, the Companions were not perfect—Mughīrah ibn Shuʿbah had lied, and Walīd ibn ʿUqbah was a known drunkard. But none had ever lied about the Prophet ﷺ.
Many Sunni scholars have thus understood uprightness as meaning that the Companions’ exposure to the tremendous spiritual charisma of the Prophet prevented them from lying about him but did not prevent other sins.
It is no surprise, then, that Sunni hadith scholars strove to identify who was a Companion. ʿAlī ibn al-Madīnī (d. 234/838) wrote an early work (now lost) listing them, to be followed by Ibn Qāniʿ (d. 351/962), Abū Nuʿaym al-Iṣbahānī, and others. Ibn Ḥajar al-ʿAsqalānī’s Iṣābah fī maʿrifat al-ṣaḥābah
is the most widely cited biographical dictionary of
the Companions. There was great disagreement over the actual number of Companions: al-Shāfiʿī estimated their number at sixty thousand, Abū Zurʿah al-Rāzī at over a hundred thousand. In his biographical dictionary of Companions, Ibn Ḥajar listed approximately twelve thousand three hundred. On a practical level, the Companions who actually played a noticeable role in hadith transmission were far fewer: the Six Books include hadiths from only 962 Companions.
The Sunni critics’ view of the Companions was both ideologically driven and practical. Islam was built on the idea that the Companions of the Prophet ﷺ had inherited his authority and passed on his teachings reliably. In that sense, as a group they were above reproach. In terms of hadith criticism, however, the critics’ reach did not extend far enough back to apply the rules of transmitter criticism to the Companions. The earliest critic, al-Zuhrī, had met only the youngest of the Companions, and his hadith criticism mostly addressed the reports he heard from other Successors. Al-Zuhrī, Mālik, and Shuʿbah had direct experience with the Successors, but they had no real way to evaluate the uprightness or accuracy of Companions. In a sense, reports such as Aisha’s aforementioned rejection of hadiths for content reasons represent vestiges of hadith criticism from the Companion generation.
The chicken and the egg: Who made the early experts experts?
The names of the early generations of master hadith critics (Figure 2) overlap to a large extent with those of major hadith transmitters. So did just transmitting a vast number of hadiths make a person a reliable hadith transmitter or an expert critic? The answer seems to be no—just because one was a major transmitter did not mean that one was reliable. Ibn Isḥāq was an essential pivot of hadith transmission in Medina, but it became clear to many critics even in his own lifetime that he was not at all discriminating in what he transmitted. Mālik, on the other hand, only transmitted from two people (ʿAbd al-Karīm ibn Abī al-Mukhāriq and ʿAtāʾ al-Khurāsānī) that he (and later critics) did not feel were reliable (thiqah). Later critics also distinguished between an early critic/transmitter’s own transmissions and his evaluations of others. Al-Zuhrī’s opinions carried great influence, but later critics all agreed that his mursal hadiths (see below for a discussion of this term) were too unreliable to use. The great critic Sufyān al-Thawrī regularly narrated hadiths that others considered unreliable, whereas when Shuʿbah transmitted a hadith, it was understood that he believed it was authentic.
In a similar vein, in the formative period of Sunni Islam in the ninth century, did hadith scholars such as Ibn Ḥanbal decide which early transmitters to accept based on their Sunni beliefs? Was Sunni hadith criticism just a tool for excluding non-Sunnis? The answers to these questions are certainly ‘no,’ since, as we have seen, Sunni critics regularly accepted the hadiths of people whose beliefs they considered anathema. Beyond merely accepting non-Sunnis as transmitters of hadiths, Sunnis even accepted one as a hadith critic
. Despite his fervent Shiism, Ibn ʿUqdah (d. 332/944) was listed by staunch Sunnis like al-Dhahabī as “the oceanic hadith scholar,” whose criticisms of transmitters and narrations carried great weight.
2) Contiguity of transmission (al-ittiṣāl)
Evaluating the sources of a hadith was of little use, however, if a critic could not be sure who these sources were. If one transmitter had never actually met the person from whom they quoted the hadith, or if it was known that he had not heard that hadith from his teacher, then who was the intermediary? With no way to guarantee that intermediary’s reliability, there were endless possibilities for what sort of deviation or forgery could have occurred. Establishing that a hadith had been transmitted by a contiguous, unbroken isnād from the Prophet ﷺ was thus as crucial as transmitter reliability for determining the authenticity of a hadith. If it could not be established that the people in the isnād had heard from one another, then hadith critics considered the chain of transmission broken (munqaṭiʿ) and thus unreliable.
In order to determine if an isnād was ‘contiguous’ (muttaṣil), hadith critics attempted to identify all the people from whom a narrator had heard hadiths. If a transmitter was not a known liar, then one could infer this from his saying “So-and-so narrated to me” (ḥaddathanī), “So-and-so reported to us” (akhbaranā), or “I heard from so-and-so” (samiʿtu min...). Other phrases for transmission did not necessarily indicate direct transmission. “According to” (ʿan) could mean that someone had heard a hadith directly from the person in question or not. In addition to looking at this terminology, a critic would compare the death date of the teacher with the age of the student and investigate the possibility that they were in the same place at the same time.
Because establishing contiguous transmission was so important, by the mid 700s transmitters had become very serious about specifying exactly how hadith transmission occurred. The most accurate forms of direct transmission were either reading a teacher’s hadiths back to him (often indicated by the phrase “he reported to us” (akhbaranā’)) or listening to the teacher read his hadiths (often indicated by “he narrated to us” (ḥaddathanā’)). If a teacher gave a student his books of hadiths to copy, this was termed “handing over” (munāwalah). Although there was debate over whether reading hadiths to a teacher or hearing them read was more accurate, all scholars acknowledged that ‘handing over’ and liberal ‘permission to transmit’ were the most tenuous forms of transmission. Reading a book with no transmission from the teacher at all (“finding” (wijādah)) inspired no confidence at all.
Transmitters fretted over these forms of narration and often debated the proper terminology. The Ḥanafī al-Ṭaḥāwī (d. 321/933) wrote a short treatise on how the technical terms ‘akhbaranā
’ and ‘ḥaddathanā’
actually meant the same thing (also the opinion of the majority of scholars). When al-Awzāʿī gave a book of hadiths to a student in an act of ‘handing over,’ the student asked, “About this book, do I say ‘ḥaddathanī
’?” Al-Awzāʿī replied, :”If I narrated it directly to you, then say that.” The student inquired, “So do I say ‘akhbaranī
’?” Al-Awzāʿī replied that no, he should say “al-Awzāʿī said” or “according to al-Awzāʿī.”
Not all critics agreed on the requirements for a contiguous isnād. There was disagreement over whether the phrase “according to” (‘an ) should be interpreted as an indication of direct transmission or not. Muslim ibn al-Ḥajjāj claimed that the great hadith critics had all accepted ʿan as indicating direct transmission provided that the two people involved were contemporaries and that it was likely that they had met one another. Others, like Ibn ʿAbd al-Barr (d. 463/1070) and al-Khaṭīb al-Baghdādī, claimed that hadith critics had agreed that one needed proof that the two transmitters had actually met at least once.
Obfuscation in transmission (tadlīs)
Critics of the eighth, ninth, and early tenth centuries often attempted to be more exact than just establishing if two transmitters had met. They sought to determine exactly which hadiths certain transmitters had heard from their teachers. Shuʿba thus studied the hadiths of his teacher Qatādah until he found that he had only heard three from his teacher Abū al-ʿĀliyah.
This was especially important in the case of tadlīs
, or obfuscation in transmission. Tadlīs
occurred when a transmitter cited an isnād
in an ambiguous manner, such as saying “so-and-so said,” implying that he had heard the hadith directly from the person when in fact he was omitting his immediate source for the hadith. Transmitters might hide their immediate source because he or she was considered unreliable or espoused beliefs unacceptable in Sunni Islam. Tadlīs
did not always occur for insidious reasons. If a student had to leave a dictation session to answer nature’s call, for example, he would hear the hadiths that he had missed from a classmate. When narrating those hadiths, however, he might leave out the classmate’s name and simply say “Teacher so-and-so said.” Because tadlīs
was often innocuous, very few transmitters were totally innocent of it. Only Shuʿbah ibn al-Ḥajjāj was known to never lapse into it.
was a primary concern of critics in the eighth century and beyond. By interrogating a transmitter a critic could determine whom he omitted from isnād
s in instances of tadlīs
. Transmitters like Sufyān ibn ʿUyaynah, who only omitted the names of reliable figures, could be trusted even when doing tadlīs
. Others who often omitted the names of weak narrators, like Ibn Isḥāq, could not be relied upon unless they specified direct transmission.
Al-Khaṭīb al-Baghdādī and Ibn Ḥajar both wrote books discussing tadlīs
and those accused of it.
Similar to tadlīs was the phenomenon of mursal hadiths, or instances in which someone quoted the Prophet ﷺ without ever having met him. If a Successor or an early scholar like Mālik said “the Prophet said,” this was clearly an incomplete isnād since Mālik never met the Prophet ﷺ. Mursal hadiths occurred because, especially in the first few generations of Muslims, scholars were not obsessive about providing detailed isnāds for every report all the time. Al-Zuhrī, Mālik, or Abū Ḥanīfah might quote the Prophet while discussing a legal issue informally without bothering to provide an isnād.
When such mursal
hadiths were recorded in muṣannaf
works like the Muwaṭṭaʾ
or the legal responses of Abū Ḥanīfah, however, they presented a problem for later hadith critics. How should they be treated? Because mursal
hadiths had incomplete isnād
s and one could not be sure from whom a Successor was narrating, mursal
s were almost always considered unreliable by hadith critics. After extensive research on the mursal
reports of certain early transmitters, however, and attempts to find counterparts to them with full isnād
s, critics approved of certain transmitters’ mursal
hadiths. Al-Shāfiʿī concluded that the mursal
s of the Successor Saʿīd ibn al-Musayyab (d. 94/713) were reliable because the source he omitted, his father-in-law Abū Hurayrah, was the most knowledgeable Companion about hadiths. Critics debated the reliability of al-Ḥasan al-Baṣrī’s mursal
hadiths—his contemporary Ibn Sīrīn said that al-Ḥasan was totally uncritical about his hadith sources, so his mursal
were useless. Yaḥyá al-Qaṭṭān said that he had studied all of al-Ḥasan’s mursal
s and found versions with full isnād
for all but two of them.
Ibn Abī Ḥātim al-Rāzī composed a whole book entitled Kitāb al-marāsīl
(The Book of Mursals) in an attempt to determine which Successors had heard hadiths from which Companions.
Step three: Finding corroboration for the hadith
Corroboration had played a central role in determining the reliability of a transmitter—if he narrated hadiths that other students of his source did not, then his reliability was questioned. But a forger could still simply take an isnād of a respected transmitter and attach it to a freshly concocted hadith. The third and final step in hadith criticism thus involved looking for corroboration for the hadith itself.
Corroboration took two general forms (see Figure 3). Since a ‘hadith’ was generally associated with the Companion who narrated it, another version of the same Prophetic tradition transmitted by a second Companion or an instance of the Prophet ﷺ saying something similar on another occasion were both considered corroboration for a hadith. Such a report was termed a “witness” (shāhid). When one transmitter corroborated the report related by another transmitter that they had both heard from a common source, this was termed a “parallelism” (mutābaʿah). Hadith scholars described these two forms of corroboration with the aphorism “parallelism bolsters the narration; a witness bolsters the tradition.” A witness report need not be exactly the same tradition as the hadith it supports. Even a report with a different wording but the same meaning corroborated the fact that the Prophet ﷺ had expressed a certain idea or sentiment. Parallelisms solidified the reliability of a particular narration of a hadith.
A famous tenth-century hadith critic, Ibn Hibbān, describes the process of searching for corroboration (called iʿtibār, ‘consideration’) thus:
Let us say we come across [the transmitter] Ḥammād ibn Salamah, and we see that he has narrated a report from Ayyūb [al-Sakhtiyānī], from Ibn Sīrīn, from Abū Hurayrah, from the Prophet ﷺ, but we do not find that report from anyone else from the students of Ayyūb. What is required of us now is to refrain momentarily from criticizing Ḥammād, and to consider what his contemporaries narrated. So we must start by looking at this report: Did Ḥammād’s students in general narrate it from him, or just one of them? If it is the case that his students narrated it from him, then it has been established that Ḥammād really did narrate that report, even if that comes through a weak narrator from him, because that narration is added to the first narration from Ḥammād. So if it has been established correctly that Ḥammād narrated a report from Ayyūb that is not corroborated by others, again we must pause. For it does not follow automatically that there is some weakness here, but rather we must ask: Did any of the reliable transmitters (thiqāt) narrate this report from Ibn Sīrīn other than Ayyūb? If we find one, then it has been established that the report has some basis (aṣl yarjiʿu ilayhi). If not, then we must ask: Did anyone from among the reliable transmitters narrate this report from Abū Hurayrah other than Ibn Sīrīn? If such a narration is found, then it has been established that the report has a basis (aṣl). If not, we ask: Did anyone narrate this report from the Prophet ﷺ other than Abū Hurayrah? If so, then it has been established correctly that the report has some basis. But when that is not the case, and the report contradicts the compilations of these three [people at three levels in the isnād], then it is established without a doubt that the report is forged, and that the lone person who narrated it forged it.
As Ibn Ḥibbān describes, if a report is not corroborated at any one level of the isnād, then the reliability of that transmitter’s narration from his source is dubious. If the report is uncorroborated at all levels of the isnād, then it is almost certainly totally baseless. If a report was not corroborated either at some level of the isnād or from the Prophet ﷺ in general, early hadith critics deemed it “unknown/unacceptable” (munkar).
Here we see that Muslim critics worked backwards in time when authenticating hadiths. What probably first occurs to readers today is that an isnād ‘starts’ with the Prophet and ‘ends’ when the hadith is recorded in a book. But this assumes that the hadith actually existed in the time of the Prophet and that we are merely tracing how it came to us. For a Muslim hadith critic, a hadith was at first just an unverified claim; its isnād began with the person who told him the hadith. It only extended backward in time when the critic verified each link in the isnād, step by step, until it “reached” (waṣl) the Prophet ﷺ.
Of course, this process of demanding corroboration took context into consideration. As Muslim ibn al-Ḥajjāj informs us, “If it has been established that your hadith corpus agrees with those of the other reliable narrators, then narrating some uncorroborated material is acceptable.”
If a transmitter studied with a certain teacher for ten years, then it is not surprising that he might narrate a selection of hadiths from his teacher that students who only studied with him for six months did not recount. The great critic Abū Ḥātim al-Rāzī was asked to criticize ʿAbd Allāh ibn Ṣāliḥ, the secretary of Layth ibn Saʿd, for having narrated uncorroborated hadiths from Layth. Abū Ḥātim replied sarcastically, “You ask me this about the closest person to Layth, who was with him on voyages and at home and spent much time alone with him?”
But, Muslim continues, if some lesser known transmitter narrated a hadith from a prolific hadith scholar like al-Zuhrī whose numerous and respected students did not recognize that hadith, then that report would be automatically declared “unacceptable” (munkar
Like our modern investigative reporter’s source, however, a transmitter could earn such a level of confidence in the eyes of critics that he could narrate uncorroborated reports without arousing concern. Critics like al-Bukhārī and Ibn ʿAdī had examined the hadiths of master transmitters like al-Zuhrī, Mālik, Ibn al-Mubārak or Qutaybah b. Saʿīd and found that they were corroborated to such a great extent that they could be relied upon for a number of uncorroborated hadiths as well. These figures were so central to hadith transmission in general that if anyone were to have heard a rare hadith, it would be them. An uncorroborated hadith narrated by an isnād
of such pillars was known as “an authentic rare” (ṣaḥīḥ gharīb
) hadith. The hadith of Mālik al-Zuhrī Anas that t
he Prophet entered Mecca upon its conquest with a mail helmet on his head and ordered the killing of Ibn Khaṭal, an infamous enemy of Islam, was known only by
. Because this hadith was narrated by transmitters whose collections of hadiths were vaster than almost any other people of their time, this hadith was considered authentic even though it was uncorroborated.
Conversely, less stellar figures inspired no such confidence. As al-Tirmidhī explained, “Anyone from whom a hadith is narrated who is accused [of poor performance in hadith] or is criticized as weak in hadiths for his lack of carefulness and numerous mistakes, if that hadith is only known through that narration, it cannot be used as proof.” So the hadith narrated by the lone isnād
of Nāṣiḥ al-ʿAjamī, from Simāk ibn Ḥarb, from Jābir ibn Samurah, from the Prophet ﷺ: “For a man to teach his child proper manners is better than to give a whole bushel in charity”
(laʾan yuʾaddiba al-rajul waladahu khayr min an yataṣaddaqa bi-ṣāʿ
) was considered unacceptable (munkar
neither Nāṣiḥ nor Simāk were consistently reliable transmitters.