The point of departure for Hans-Thomas Tillschneider's Typen historisch-exegetischer Überlieferung is the question of how academic scholars should understand the concept of “occasions of revelation” (asbāb al-nuzūl). Academic scholars have long relied on this concept in their efforts to establish a historical context for Quranic material. Yet, and as Tillschneider points out, they did not develop the notion of asbāb al-nuzūl through a critical reading of the Quran or early Islamic literature. Instead they inherited it from the Islamic tradition that, during the prophetic career of Muhammad, God would send the angel Gabriel down from heaven with revelations germane to the particular circumstances that the Prophet encountered. Western scholars edited out the roles of God and the angel Gabriel, but they held on to the notion of asbāb al-nuzūl. Presumably most Western scholars assumed (although they generally do not make such assumptions explicit) that it was Muhammad himself who (consciously or unconsciously) came up with “revelations” that he found appropriate for particular circumstances.

In Typen historisch-exegetischer Überlieferung Tillschneider argues that the idea of asbāb al-nuzūl does not reflect the manner in which the Quran was proclaimed or written. Instead it was developed in the ninth century as a response to criticism from ḥadīth-minded scholars that the mufassirūn read the Quran only in light of their personal opinions (ra'y). This conclusion is suggested by the limited number of verses for which asbāb al-nuzūl traditions are found (Tillschneider relates on p. 15 that such traditions are found for less than 10 per cent of the Quran; cf. p. 256). If the Quran were fundamentally the product of one man's proclamations in response to the circumstances in which he found himself, we might expect to find traditions explaining the circumstances behind most – if not all – of its passages. Instead what we seem to find are traditions for certain passages which by their literary quality allowed medieval Muslim scholars to create fitting narratives.

This point has been made by Andrew Rippin (who emphasizes, among other things, the existence of distinct asbāb al-nuzūl narratives for different readings of the same Quranic passage). Nevertheless, the continued reliance of academic scholars on asbāb al-nuzūl is justification enough for Tillschneider's new treatment of this matter. Furthermore, Tillschneider's work addresses unexplored questions surrounding the notion of asbāb al-nuzūl. Much of Typen historisch-exegetischer Überlieferung is dedicated to a reconsideration of how and why medieval scholars developed this notion. Whereas Rippin (by Tillschneider's telling) argues that asbāb al-nuzūl narratives were above all exegetical (products of an effort to render the Quran more meaningful), Tillschneider argues that they were originally historical (and connected to the origins of ḥadīth literature).

In chapter 1 (“Typen historisch-exegetischer Überlieferung”) Tillschneider meticulously analyses the character and function of reports included by Muslim scholars (such as Wāḥidī and, later, Suyūṭī) under the label asbāb al-nuzūl. He notes that such reports do not, as is often assumed, necessarily involve a description of the moment in Muḥammad's life when a passage was revealed to him, but may instead provide a quasi-historical narrative connected to that passage (thus the sabab al-nuzūl for Q 105 [al-Fīl] is the birth of the Prophet). Tillschneider also notes here reports created by the insertion of a Quranic verse into a pre-existing narrative, such as the story of the first revelation given to Muhammad on Mt. Ḥirāʾ (“sicherlich bleibt die Einfügung des Verses in den Bericht für das Verständnis des Verses nicht ohne Konsquenzen, doch das ist ein sekundärer Effect”, p. 41).

The second chapter (“Literarische Milieus”) is an investigation into the historical genesis of individual asbāb al-nuzūl reports. Tillschneider argues here that sīra and early tafsīr are shaped by the application, and interaction, of Quranic passages and pre-existing historical traditions (to this end he argues against the idea that sīra is substantially the product of exegesis: “Die Handlungsrahmen stützt sich in Wesentlichen auf außerkoranische Informationen”, p. 138). However, the idea of asbāb al-nuzūl – i.e. of explaining why God revealed certain passages through the citation of traditions about Muhammad – is absent from this earlier literature. It appears only with the classical ḥadīth collections of the third/ninth century, and then as a response to the criticism of tafsīr “eine Instanz der Konstellation ḥadīṯ und sunna gegen ra'y” (p. 237).

In the following chapter (“Der Korantext und seine Anlässe”) Tillschneider questions the cogency of academic reliance on the idea of asbāb al-nuzūl reports by examining the internal evidence of the text. He notes, first, that nothing in the Quran makes this idea compelling. The Quran's dialogical nature might be attributed to a literary technique (and not to actual conversations that were later documented and later recorded); its fragmentary quality might be attributed to a redaction process (and not to the joining of different revelations from distinct historical moments).

Thereafter Tillschneider addresses this matter through an analysis of the frequency per Sura of nuzūl traditions reported by Wāḥidī. The rate of nuzūl traditions for Suras that Nöldeke classes as Medinan (15.6 per cent) is higher than for the others (Mecca 1: 7.3%; 2: 3.5%; 3: 4.6%). To Tillschneider this is because those Suras frequently contain material (presumably it was this commonality that led them to be grouped into one “chronological period” in the first place) that could easily be joined with historical reports: “Die Koran/Geschichtsverknüpfungen, die den nuzūl-Überlieferungen zugrunde liegen, sind ganz ursprünglich das Resultat einer historiographischen Nachlese im Koran-text” (p. 255). This material, Tillschneider proceeds to show, includes specific terms such as “farīq”, “ṭā’ifa”, and “min al-nāsi [or “minhum”] man” that allowed this joining to take place. In the second half of this (dense, and carefully argued) chapter Tillschneider illustrates that the manner in which Angelika Neuwirth divides “Meccan” Suras, and the manner in which Richard Bell divides “Medinan” Suras, does not match the divisions suggested by asbāb al-nuzūl traditions.

In the fourth chapter (“Koran wird zu ḥadīṯ”) Tillschneider turns to the question of the origin of asbāb al-nuzūl traditions towards the end of the second Islamic century, arguing that their rise is related to the rise of prophetic ḥadīth. Fuqahā”, such as Shāfiʿī insisted that only valid prophetic ḥadīth might play an authoritative role in legal thinking. In a similar way the fuqahā’ privileged interpretations of the Quran which involved the Prophet Muhammad, and thereby asbāb al-nuzūl traditions began to appear. Thus asbāb al-nuzūl traditions were originally the stuff of jurisprudence: “Was später der Korankommentar (tafsīr) unter dem Begriff asbāb an-nuzūl für sich beansprucht, ist für aš-Šāfiʿī noch reine Prophetenüberlieferung, zwar eine Überlieferung davon, wie der Prophet Koranverse geäußert hat, nichtsdestotrotz aber keine exegetische Überlieferung, sondern Koranḥadīṯ” (p. 354).

The fifth and final chapter (“Die Literaturgattung ʿasbāb an-nuzūl”) is dedicated to an investigation of the later development of the literary genre of asbāb al-nuzūl. Tillschneider begins therein by tracing the isnāds for the traditions cited by Wāḥidī (d. 468/1076), author of the earliest extant work explicitly dedicated to asbāb al-nuzūl. Thereby he concludes that interest in asbāb al-nuzūl first arose in the context of Sahl b. ʿUthmān (d. 235/849–50), the authority from whom forty different traditions are transmitted to Wāḥidī through the same three figures. Sahl b. ʿUthmān was a contemporary of ʿAlī al-Madīnī, the teacher of Bukhārī, to whom the first work on asbāb al-nuzūl is attributed. By Tillschneider's understanding this suggests that the concept of asbāb al-nuzūl was born along with the concept of prophetic ḥadīth and of the sunna as a second source of revelation. By Wāḥidī's day Sunni scholars had found in asbāb al-nuzūl traditions a way to respond to esoteric exegesis of the Quran (Tillschneider suggests that a particular concern was Shiite exegesis – including the bāṭinī exegesis of the Ismāʿīliyya who were a political threat at the time). Wāḥidī's work should accordingly be seen as part of the crystallization of Sunni Islam, centred around Nīshāpūr in the fifth/eleventh century. By the end of Tillschneider's work the reader is thus meant to see the concept of asbāb al-nuzūl as part of the development of medieval Islam, and not as a record of how the Quran was originally proclaimed.

Typen historisch-exegetischer Überlieferung is the product of careful research on Wāḥidī's work and of careful thinking about the ways in which scholars of the Quran have relied on a traditional category of medieval Islam. Tillschneider both provides useful data on the quality of the traditions in Wāḥidī's work and challenges the common reflex of scholars to turn to asbāb al-nuzūl in their discussions of the Quran. It is particularly encouraging to see Tillschneider engage the ideas of John Wansbrough, a figure too often ignored (particularly in the German context). Typen historisch-exegetischer Überlieferung bears the marks of a doctoral dissertation: it is long, dense, and at times repetitive. Despite this it leaves some questions unanswered. For example, if asbāb al-nuzūl reports involve the application of historical traditions to the Quran (more than haggadic exegesis), then what is the origin of these traditions? In addition, Tillschneider includes an index of authorities who figure in the Wāḥidī's work, but not indexes of subjects, people, or Quranic verses. On the whole, however, Typen historisch-exegetischer Überlieferung is an important work, and one that poses a challenge to the assumptions that are still prevalent in the field of Quranic studies.