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Schadler, Peter, John of Damascus and Islam: Christian Heresiology and the Intellectual Background to Earliest Christian-Muslim Relations

Diego Sarrió Cucarella
p. 390-394
Bibliographical reference

Schadler, Peter, John of Damascus and Islam: Christian Heresiology and the Intellectual Background to Earliest Christian-Muslim Relations, coll. The History of Christian-Muslim Relations, 34, Leiden, Brill, 2018, 264 p.

Full text

1The obvious importance of John of Damascus (d. ca.749) in the history of ­Muslim-Christian relations derives from the fact that he was the first major ­Christian intellectual to confront Islam. As is well known, John’s short treatise on Islam, or, more accurately, on “the people-deceiving cult (thrēskeia) of the Ishmaelites”, ­appears in the last chapter of his book On Heresies, itself one of three parts of a larger work entitled The Fount of Knowledge (Pēgē gnōseōs), intended as a summary presentation of the Christian faith. According to Schadler, many modern scholars have come to quick and mistaken assumptions about what John’s placement of his work on Islam in a book on heresies implies, namely that he perceived Islam as a Christian heresy. As Schadler sees it, no attempt has been made to properly understand John’s position in the Christian theological tradition of heresiological discourse, nor has an effort been made to place him in his historical context with reference to more recent scholarship in the field of Islamic studies, two shortcomings Schadler intends to remedy, at least in part.

2Thus the first two chapters of the book situate John of Damascus in both his historical context and in the literary context of the Christian heresiological tradition, this in view of properly understanding his perception of Islam and his actual intention. Chapters 3 and 4 are a forceful attempt to show that we have no evidence that enables us to hold that John gave a deliberately distorted view of Islam or that he fabricated characterizations of the Ishmaelites for polemical purposes. On the contrary, Schadler believes that John was attempting to offer an accurate picture of Islam and that his knowledge of this religion might not have been as limited as previous scholars have often imagined. A common error of such scholars, according to him, has been to assume that John was in contact with “a normative monolithic Islam”, an assumption that contrasts with the most recent scholarship in the field of Islamic studies, which challenges the existence of a normative Islam as early as John’s time. In fact, according to Schadler, if anything, John’s perspective on Islam is corroborated by parallels found in the literature, both Islamic and ‘para-Islamic’, of his time. For Schadler, scholars such as John E. Merill, John Meyendorff, W. Montgomery Watt, Daniel Sahas, Raymond Le Coz and, in a lesser measure, Andrew Louth, have committed the anachronistic fallacy of evaluating John’s understanding of Islam on the basis of the Islam we know today.

3Chapter 1 (‘Heresy and Heresiology in Late Antiquity’) begins by noting that John’s inclusion of the Ishmaelites in his heresiology was an oddity. Christian authors of his period and after regularly referred to the Muslims as pagans rather than as heretics. This was the result of an understanding of the term heresy, today well established, which sees heresy as having its origins within the Church, in the sense that it entails a wilful departure from Christian faith (at least as interpreted by the ‘orthodox’ party). We can recall here Origen’s statement that “all heretics at first are believers; then later they swerve from the rule of faith” (cited on p. 24). As Schadler reminds us, the tradition of including pre-Christian groups in heresiologies represents a far weaker heresiological tradition than that which situated the beginning of heresy in Simon Magus (see Acts 8: 9‒24). When pre-Christian groups were included, this was often limited to groups that were contemporary with Christ, and done to identify them as being directly opposed to him, or the result of theologically pre-dating the origins of the Church to coincide with the origins of humanity and presenting Adam as a proto-Christian (e.g. Epiphanius of Salamis, d. 403). And hence the apparent oddity which John of Damascus’s inclusion of Islam in his book of heresies represents, given that he does not appear to consider Islam to have originated within the Church, nor Muḥammad to have been a Christian in his earlier life.

4This oddity is softened, Schadler contends, if we consider that John’s notion of heresy was a more complex one. Although he was certainly aware of the definition of heresy as a wilful departure from the Church’s rule of faith, in the Dialectica, the first part of The Fount of Knowledge, he expresses another understanding of heresy derived from the Neoplatonist philosophical tradition, namely heresy as “a persuasion, or opinion (δόζα), held by several persons in agreement with each other but at variance with others” (cited on p. 85). According to Schadler, it is in the latter sense that John of Damascus may have considered Islam a heresy. There is no evidence, he contends, that John saw Islam as a specifically ‘Christian heresy’, in the sense of Origen’s statement quoted above. Moreover, if it is true that The Fount of Knowledge was intended to be read from cover to cover, as Schadler argues, this suggests that John expected his readers to read his definition of heresy in the Dialectics before they went on to read his book On Heresies.

5It is here, I think, that Schadler does not consider sufficiently John’s claim that Muḥammad may have learned what he knew of Christianity from a possibly Arian monk. Schadler quickly dismisses the claim as offering “very limited evidence for any view that John conceived of Islam in the terms described above” (p. 32), that is, as an insider’s wilful departure from the Church’s rule of faith, or at least by someone connected with someone else who had been an insider (see p. 47 for the notion of genealogical succession of heresies, paralleling the apostolic succession in the handing down of the true faith). In Schadler’s reading, John attaches no particular significance to his own claim. Yet Schadler himself notes elsewhere in his book that John (as well as his intellectual disciple, Theodore Abū Qurra, d. ca.830) insisted on associating Muḥammad’s instructor with Arianism, while other Christian writers favoured more plausible alternatives, such as Nestorianism. Could it not be that, as far as the Qur’ānic depiction of Jesus is concerned, John was indeed convinced that the prophet of the Ishmaelites held “an intellectually defective vision of the Christian faith, having its origins within the church”, to use Alister McGrath’s definition of heresy (cited on p. 22), similar to that of Arius? Were this the case, it would not necessarily invalidate other good points that Schadler makes, as, for instance, that John was operating with a more complex understanding of heresy than other ­Christian writers of his time. Nor would it contradict Schadler’s interpretation of John’s overall intention for including Islam in his heresiology (on which more later). For this reviewer, it is problematic to suggest, as Schadler does, that while Muḥammad may be responsible for certain beliefs among the Ishmaelites, he was not their sole source of authority and that they “may have their own reasons for certain beliefs about the person Jesus” (p. 93). Schadler is moving here into highly speculative terrain. Whatever may have been the Ishmaelites’ beliefs about Jesus prior to the arrival of Muḥammad, what we know for sure is that John ascribed to the “false prophet” who had appeared in their midst claiming to have received a scripture from heaven the view that “Jesus was created and a servant [of God],” and that he was not crucified, nor did he die, but was raised up to heaven, all of which would certainly qualify as a ‘Christian heresy’ in the more restricted sense of the term.

6At a certain point, Schadler recalls Fred M. Donner’s recent theory regarding the origins of Islam as a monotheistic reform movement—“the Believers’ ­movement”—which would have initially included Christians and Jews, and from which Islam would have eventually emerged as a new and distinct religious group, well after the death of Muḥammad (page 32, n. 44). Schadler considers that, in any case, Donner’s hypothetical reconstruction of the beginnings of Islam no longer applied in John of Damascus’s time, when confessional identities were clearly defined. While he may be right in this assumption, Islam’s reclaiming of the Abrahamic faith and the incorporation of Jesus, son of Mary, into its own version of salvation history, with a significantly different role from that accorded to him in Christianity, could have been grounds for including the post-Muḥammad Ishmaelite ‘thrēskeia’ in a Christian heresiology, as people who, while claiming insider status, rejected the ‘orthodox’ faith. In fact, Muslims have often characterised themselves as the true followers of Christ. A further argument for the plausibility of including Islam in a Christian heresiology is John of Damascus’s remark that the “false prophet” Muḥammad had chanced upon the Old and New Testaments before contriving his own heresy, a remark that Schadler completely ignores.

7Incidentally, John of Damascus’s comment that Muḥammad’s instructor was an Arian monk appears again, in a positive light, in medieval Muslim anti-Christian literature, which saw in Arius the defender of the true nature of Christ—that of a mere creature—against the doctrinal “corruption” introduced at Nicaea and sanctioned in its creedal formulation: “True God from true God, begotten, not made, of one substance with the Father.” Some legendary reports tell the story of a group of Christians who, wishing to remain loyal to Christ’s original message, fled to Arabia. Later, Muḥammad met thirty monks from among them. They followed him and died Muslims.

8For this reviewer, Schadler’s most stimulating proposal is found in chapter 2 (‘Aspects of the Intellectual Background’), where he discusses John of Damascus’s possible reason for including Islam in the last chapter of his book On Heresies. One important point made in this chapter is that, unlike other similar compendia of knowledge written at the time, John intended The Fount of Knowledge to be studied and learned, not simply referenced when in need of a quotation to support a specific viewpoint. In other words, the Fount was meant to be read from cover to cover, as a three-part work, composed in view of facilitating theological education “in a hostile environment outside of the protection of Constantinople and among the many competing forms of Christianity” (p. 55). According to Schadler, John felt the need to include a heresiology in this project to serve “as an alternative form of the history of the world, written as a triumph of Christianity over error, whether theological or ‘pagan’ philosophical” (p. 60). In this view of history—more credible, given the circumstances, than Eusebius of Caesarea’s Ecclesiastical History, in which Christian truth was linked to the political success of the Roman Empire —the Ishmaelites needed to be incorporated as the “final bringers of an alternative system of faith and communal order into the political sphere of the empire” (p. 62). Indeed, “placing them in the hundredth and last position accorded well with the common belief at the time that they were the initiators of the coming Apocalypse” (p. 62). To put it differently, in the highly adverse milieu of 8th-century Syria and Palestine, in which Chalcedonian Christians no longer enjoyed the protection of the Byzantine imperial establishment, it seemed crucial to John of Damascus to reassure the members of his community by providing them with a refutation of all alternatives, including Islam. As Schadler writes: “The process by which the full historical market of alternative possibilities is excluded, so that, by process of elimination, that which remains must be the truth, was not possible without the inclusion of the beliefs of the Ishmaelites in his heresiology, regardless of whether or not they satisfied typical traditional criteria for heresy” (p. 64). A similar intention can be discerned in Theodore Abū Qurra, studied in chapter 5 of Schadler’s book, in whose writings “the full range of religious alternatives are presented to be refuted, and Christianity is contrasted to all of them, regardless of how they came into existence” (p. 63).

9On the negative side, it is unfortunate that the book did not receive a more careful editorial revision before its final printing. Some of the material in the introduction, including several footnotes, is reproduced verbatim in later pages. Also, an inconsistency difficult to explain is the fact that the citations from John of Damascus’s chapter on Islam in the main text of the book do not always correspond with the author’s own translation of the original Greek text provided in Appendix 1 (p. 218‒233). Finally, although other writings supposedly by John of Damascus commenting on Islam are discarded from Schadler’s analysis on the grounds that there is no final agreement on their authorship, the so-called Dialogue between a Saracen and a Christian, given its long-standing association with the Damascene, could have been presented and compared, even if briefly, with John’s passage from On Heresies. These criticisms notwithstanding, Schadler’s book is an important and worthy contribution towards advancing our understanding of John of Damascus’s perception of Islam and, more generally, the intellectual and social context in which he lived and wrote.

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Bibliographical reference

Diego Sarrió Cucarella, “Schadler, Peter, John of Damascus and Islam: Christian Heresiology and the Intellectual Background to Earliest Christian-Muslim RelationsMIDÉO, 34 | 2019, 390-394.

Electronic reference

Diego Sarrió Cucarella, “Schadler, Peter, John of Damascus and Islam: Christian Heresiology and the Intellectual Background to Earliest Christian-Muslim RelationsMIDÉO [Online], 34 | 2019, Online since 10 June 2019, connection on 21 January 2022. URL:

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