The study of hadith narrators (ʿilm al-rijāl) arose in the 2nd century AH as hadith scholars worked to identify and catalog the names of narrators, searching for their stories and scrutinizing their conditions. The oldest compilations of this field of study may date back more specifically to the second half of this century. Regardless, by the 3rd century AH, a significant increase had occurred in authorship on the subject. As a consequence, authors began to focus their texts on one of the many subfields that came to make up the larger study of hadith narrators: biographies, histories, studies assessing the reliability of narrators (al-jarḥ wa al-taʿdīl), and compilations of names and surnames. As leading scholars continued to develop this genre, delving into the histories and affairs of narrators, it was only a matter of time before they came across narrators who shared the same names. They found that two narrators may have the same first name and father’s name, first name and family name, first name and kunya [honorific], kunya and family name, or the like. The question therefore recurred in scholars’ minds of how to determine when to combine (al-jamʿ) and when to differentiate (al-tafrīq) narrators with the same names; in other words, when to consider them as the same person or as separate people.

At the same time in the 3rd century AH, the composition of books relating to the Sahaba (the companions of the Prophet Muhammad) had appeared, taking various forms. Some authors such as Bukhari (d. 256) and Ibn Abi ʿĀṣim (d. 287) chose to focus entire texts on the Sahaba, while others including Ibn Saʿd (d. 230), Khalīfa bin Khayyāṭ (d. 240), and again Bukhari included sections on the Sahaba within their larger texts of biography or history. In both of these kinds of books, the authors are found to have also dealt with the question of combination and differentiation (al-jamʿ wa al-tafrīq) of shared names.

This problem appeared so frequently that scholars who’ve tackled it over the years first dedicated specific terminology to it (i.e., al-muttafiq wa al-muftariq [the alike and the unalike]) and then built a whole sub-genre dedicated to it under the broader field of hadith studies. One must not look any further for examples than Kitāb al-Muttafiq by Abu Bakr al-Jawzaqī (d. 388 AH) or Kitāb al-Muttafiq wa al-Muftariq by al-Khaṭīb (d. 463 AH), amongst others. This increased literary activity led to scholars criticizing and questioning each other’s positions on the subject. For example, al-Khaṭīb’s Muwaḍḍiḥ Awhām alJamʿ wa al-Tafrīq disputed Bukhari’s Al-Tārīkh al-Kabīr. He argued that Bukhari had mistakenly combined two disparate individuals into a single biographical entry in one instance while dedicating two biographical entries to a single person incorrectly in another.

This study aims to give careful consideration to this issue of al-jamʿ wa al-tafrīq in books dedicated to the Sahaba specifically. It uncovers the perceptiveness of the authors of this genre and the particular attention they paid to solving this matter, both in theory and in practice. This study further aims to identify their tendencies toward either narrowing or expanding, namely whether they tended to consider narrators with shared names as a single individual or as separate individuals. This article will evaluate the efficacy of their approaches toward resolving this issue as a whole by focusing on the most significant and prominent texts. These are: Maʿrifat al-Ṣaḥāba by Ibn Manda (d. 395 AH), Maʿrifat al-Ṣaḥāba by Abu Nuʿaym al-Asfahānī (d. 430 AH), al-Istiʿāb fi Maʿrifat al-Aṣḥāb by Ibn ʿAbd al-Barr (d. 463 AH), Asad al-Ghāba by Ibn al-Athīr (d. 636 AH), and Al-Iṣāba fi Tamyīz al-Ṣaḥāba by Ibn Hajar (d. 852 AH).

This article is not an applied study that determines whether specific biographies of the Sahaba tended toward combining or differentiating those with shared names or that concludes by determining which approach is more compelling. This is also not a study whose goal is to encompass every single example of al-jamʿ wa al-tafrīq in order to end up with an integrated methodology with which to approach this problem. This study instead aims to trace the history of this issue and its development through books dedicated to the Sahaba. It will identify the various ways that the authors of these texts had treated companions with shared names and will evaluate the effectiveness of their perspectives as a whole. It will also pave the way for more specialized studies on the approaches of these authors, such as studies focused on a single one of these authors or studies comparing the approaches of two or more authors in detail. It will also facilitate future foundational studies that will outline a comprehensive methodology for approaching this issue by highlighting evidence, restrictions, perceptions, and other similar factors.

ne of this study’s conclusions has been to establish that the issue of al-jamʿ wa altafrīq had appeared early on in the very first of the compositions dedicated to the study of hadith narrators. The composition of works relating to the Sahaba was no different. As was stated previously, the issue of al-jamʿ wa al-tafrīq was also raised in the very first texts on the Sahaba in the 3rd century AH.

Another conclusion this study has reached is to demonstrate how the authors of studies on the Sahaba had varied both in terms of the extent to which they were concerned at all with al-jamʿ wa al-tafrīq, as well as their approaches to dealing with this issue. Some tended towards differentiating Sahaba with similar names into disparate personalities and rarely combined them into a single person, while others rarely differentiated names and preferred more often to combine them, and still others chose a middle path between the two. Ibn Manda is considered to have very liberally differentiated between Sahaba with shared names, while Abu Nuʿaym is considered at the opposite end of the spectrum. As for Ibn ‘Abd al-Barr, Ibn al-Athīr, and Ibn Hajar, they were all balanced in their decision to combine or differentiate. However, one could say that Ibn Hajar had leaned toward expansiveness in practice, as he tended to differentiate more than he combined those with shared names, even though his theoretical methodology advocated mediating between the two. While Abu Nuʿaym’s language is generally decisively in favor of combining, Ibn ʿAbd al-Barr’s is more indecisive, both with regards to combining as well as to differentiating. As for Ibn al-Athīr and Ibn Hajar, their explanations stand out for their ability to detail degrees of decisiveness that reflect their careful consideration in determining when to combine or differentiate.

This study also concludes that Ibn Manda had not concerned himself at all with this issue, let alone demonstrated any method on how to approach it. Abu Nuʿaym instead was the first to illustrate a method for dealing with this problem when considering only those books relating to the Sahaba, not to those covering the study of narrators more broadly. Abu Nuʿaym offered circumstantial evidence, both explicitly and implicitly, and advocated combining two biographical entries. He did not offer any evidence with regards to differentiating two persons with shared names, as he never did so himself, though one may find instances when he simply upheld a previous author’s differentiation between two persons. Ibn ʿAbd al-Barr expanded this methodology by sharing circumstantial evidence for both when to combine and when to differentiate. His evidence is clearer and more explicit than Abu Nuʿaym’s in terms of combining, and he also included examples of when to differentiate. One can say that this methodology then reached the pinnacle of its development in the hands of Ibn al-Athīr and Ibn Hajar, for they demonstrated how to use circumstantial evidence for either combining or differentiating, and their explanations are largely similar. In most instances, the difference between the two is either that one author’s particular evidence is more general while the other’s is more detailed, or that one author chose to leave out mentioning some of the other author’s evidence, having believed it to be understood by other pieces of evidence that had been mentioned. As such, to assert that a theoretical difference exists between Ibn al-Athīr’s and Ibn Hajar’s methodologies to approaching this issue is untenable. In most instances, the two differed on whether to combine or differentiate two Sahaba with shared names due to practical and not theoretical reasons.