Abu Ḥāmid Muḥammad ibn Muḥammad al-Ghazālī

1. Introduction

Abu Ḥāmid Muḥammad ibn Muḥammad al-Ghazālī (1058–1111), known in medieval Latin as Algazel, was a Persian Sunni jurist, theologian, Sufi, and philosopher whose writings became central reference points for later Islamic intellectual history. Operating within Ashʿarī kalām and Shāfiʿī law, he is widely regarded as a pivotal figure in articulating a synthesis between formal religious sciences and Sufi spirituality.

Modern scholarship tends to characterize al-Ghazālī through several overlapping roles:

His major Arabic work, Iḥyāʾ ʿUlūm al-Dīn (Revival of the Religious Sciences), integrates ritual law, ethics, and spiritual psychology into a comprehensive program of religious life. In Tahāfut al-Falāsifa (Incoherence of the Philosophers) he attacks key Avicennian doctrines, especially concerning God, causality, and the eternity of the world. Other writings, such as al-Munqidh min al-Ḍalāl, al-Mustaṣfā fī Uṣūl al-Fiqh, and Mishkāt al-Anwār, present his views on certainty, legal reasoning, and divine light.

Interpretations of his significance diverge. Some Muslim and Western scholars present him as the “Proof of Islam” who revitalized orthodoxy; others see him as a turning point who redirected intellectual energies away from speculative philosophy. A further strand emphasizes his role as a bridge figure—appropriating, transforming, and re-situating philosophy, Sufism, and theology within a single religious vision.

This entry surveys his life, historical milieu, and major writings, and analyzes the principal elements of his metaphysics, epistemology, ethics, Sufi synthesis, and subsequent reception across Islamic, Christian, and Jewish traditions.

2. Life and Historical Context

Al-Ghazālī’s life (1058–1111) unfolded in the Seljuk period, often viewed as a high point of the medieval Islamic Golden Age. He was born in Ṭūs in Khurasan, a culturally Persian region within the broader Sunni Seljuk Empire, and spent significant periods in Nīshāpūr, Baghdad, Damascus, Jerusalem, and again near his birthplace.

Political and Institutional Setting

Under the Seljuks, political authority was intertwined with scholarly and religious elites. The vizier Niẓām al-Mulk founded the Niẓāmiyya madrasas, which became key centers for Ashʿarī theology and Shāfiʿī law. Al-Ghazālī’s later appointment to the Niẓāmiyya of Baghdad placed him at the core of these state-supported scholarly networks.

The era was also marked by:

Intellectual and Religious Climate

Several currents shaped al-Ghazālī’s agenda:

• Avicennian philosophy dominated speculative metaphysics and natural philosophy, prompting theological responses.
• Ashʿarī kalām was refining its positions on divine attributes, causality, and human action.
• Sufi networks—orders were not yet rigidly institutionalized—cultivated asceticism, dhikr, and notions of experiential knowledge (maʿrifa).

These movements sometimes conflicted but also overlapped. Al-Ghazālī’s work engages all three, variously defending, criticizing, and reconfiguring them.

Biographical Outline in Context

Al-Ghazālī’s trajectory—from provincial student in Ṭūs, to star pupil of al-Juwaynī at Nīshāpūr, to celebrated professor in Baghdad, then wandering ascetic, and finally teacher and Sufi master in Ṭūs—mirrors broader Seljuk patterns of scholarly mobility and patronage.

Historians differ on how much the political turbulence of the late 11th century (assassinations, factionalism, Crusader advances) affected his personal choices. Some emphasize his inner spiritual crisis as decisive; others highlight the pressures and opportunities generated by an imperial madrasa system seeking ideological consolidation.

3. Education and Early Scholarly Career

Al-Ghazālī’s early formation combined traditional religious study, emerging forms of systematic kalām, and an increasing familiarity with philosophical methods.

Early Studies in Ṭūs and Khurasan

Orphaned at a young age, he was reportedly placed under the care of a Sufi friend of his father, but his formal training occurred in regional circles of Shāfiʿī jurisprudence and Quranic sciences. Sources indicate that by his late teens he had already distinguished himself in fiqh and legal disputation.

Nīshāpūr and al-Juwaynī

A decisive phase began when he joined the madrasa of Imām al-Ḥaramayn al-Juwaynī in Nīshāpūr (c. 1077–1080). Under al-Juwaynī he:

• Mastered Ashʿarī kalām, including debates on divine attributes, human action, and occasionalism.
• Studied uṣūl al-fiqh, contributing later to its methodological refinement.
• Encountered logic and philosophical argumentation, as al-Juwaynī was open to some rational tools.

Contemporaries describe him as exceptionally skilled in debate, able to summarize and critique competing positions. This reputation attracted the attention of Seljuk officials and fellow scholars.

Transition to Public Scholarly Life

After al-Juwaynī’s death (1085), al-Ghazālī entered the Seljuk court milieu, especially under Niẓām al-Mulk, where he participated in scholarly disputations. Accounts portray this period as one of rapid ascent:

Modern scholars debate how deeply he had already absorbed Avicennian philosophy at this stage. Some argue that his serious engagement with falsafa came slightly later in Baghdad; others maintain that Nīshāpūr already exposed him extensively to philosophical texts.

In any case, this formative period established him as a mutakallim and jurist of high standing, setting the stage for his appointment in Baghdad and his later critical engagement with philosophy and Sufism.

4. Baghdad Period and Rise to Prominence

Al-Ghazālī’s decade surrounding his appointment in Baghdad (c. 1091–1095) marks his ascent to the pinnacle of scholarly prestige within the Seljuk Empire.

Appointment to the Niẓāmiyya of Baghdad

In 1091, under the patronage of Niẓām al-Mulk, al-Ghazālī became head professor (mudarris) at the Niẓāmiyya madrasa in Baghdad, then arguably the most prestigious teaching post in the Islamic world. Here he lectured primarily on Shāfiʿī law and Ashʿarī theology, attracting large audiences of students and jurists.

This position embedded him in:

Engagement with Falsafa and Kalām

In Baghdad, al-Ghazālī undertook a systematic study of Avicenna and other falāsifa. He produced several works on logic and philosophical methodology, such as Miʿyār al-ʿIlm and Mihakk al-Naẓar, which adapt Peripatetic logic for theological and legal purposes.

He also composed theological treatises (e.g., al-Iqtiṣād fī al-Iʿtiqād), which attempt a “moderation” between extremes in articulating Ashʿarī doctrine. Scholars see this period as one of relative confidence in rational kalām, even as he increasingly perceived its limitations for attaining existential certainty.

Public Debates and Anti-Bāṭinī Polemics

At court and in the madrasa, al-Ghazālī engaged in public disputations. He wrote refutations of Ismāʿīlī (Bāṭinī) doctrines, which the Seljuk state viewed as a political and religious threat. These polemics portray him as a defender of:

• The sufficiency of the Prophet’s law without esoteric imams.
• The compatibility of rational inquiry with Sunni revelation.

Historians disagree on how far his polemical writings merely served state agendas versus reflecting deeply held convictions. Yet there is broad agreement that in Baghdad he became a symbol of Sunni orthodoxy, while experimenting intellectually with philosophical tools that he would later critique more sharply in Tahāfut al-Falāsifa.

5. Spiritual Crisis and Withdrawal from Public Life

Around 1095, al-Ghazālī experienced a profound spiritual and intellectual crisis that led him to abandon his post in Baghdad and withdraw from public life.

Nature of the Crisis

In his later autobiographical al-Munqidh min al-Ḍalāl, he describes:

• A collapse of confidence in discursive knowledge, including kalām and philosophy.
• Intense anxiety about the sincerity of his intentions—whether his teaching was for God or for prestige.
• Psychosomatic symptoms, such as loss of speech and appetite, interpreted as signs of divine intervention.

Some modern scholars read this as a classic conversion narrative, structured literary to justify his later Sufi path. Others treat it as a relatively reliable account of genuine psychological turmoil, possibly exacerbated by political instability and court tensions.

Departure and Itinerant Asceticism

Al-Ghazālī abruptly left Baghdad, officially under the pretext of pilgrimage. He traveled through:

During this period (c. 1095–1106), he practiced Sufi disciplines: solitude, night vigils, fasting, and remembrance. He also continued to read, write, and reflect critically on discourse-centered sciences.

Intellectual Reorientation

The crisis catalyzed a shift toward valuing experiential knowledge (maʿrifa) over purely rational proofs. In al-Munqidh, he describes passing through four main “paths” to truth—theologians, philosophers, Ismāʿīlīs, and Sufis—and concludes that only Sufi practice yields transformative certainty.

Scholars debate the exact chronology of key writings from this era, especially Tahāfut al-Falāsifa and early drafts of the Iḥyāʾ. A common view is that his critical stance toward philosophy and his constructive Sufi ethics matured together during this withdrawal.

The crisis thus marks a pivotal biographical and intellectual juncture: a turn from public disputation and institutional prominence to inner reform, Sufi association, and a new literary focus on the heart, intention, and spiritual practice.

6. Return to Teaching and Late Years in Ṭūs

After roughly a decade of relative seclusion and travel, al-Ghazālī gradually returned to a more public role, while retaining his Sufi orientation.

Resumption of Teaching

Around 1106, under pressure from Seljuk authorities—especially the vizier Fakhr al-Mulk—al-Ghazālī is reported to have resumed teaching, either briefly at the Niẓāmiyya of Nīshāpūr or in nearby settings. Sources diverge on the extent of this institutional re-engagement:

Most agree that he soon settled in Ṭūs, where he established a khānqāh (Sufi lodge) and a small teaching circle that combined fiqh, kalām, and Sufi training.

Teaching Style and Audience

In Ṭūs, al-Ghazālī’s teaching appears more selective and spiritually oriented than in Baghdad. Reports state that he:

• Taught advanced students in jurisprudence and legal theory.
• Led Sufi practices for a close group of disciples.
• Insisted on the integration of knowledge and spiritual discipline.

His late works often address scholars directly, exhorting them to correct their intentions and avoid worldliness.

Late Writings and Final Years

Many of his mature syntheses are typically dated to these years:

• Reflections on heresy and orthodoxy (Fayṣal al-Tafriqa).
• Elaborations of legal theory (al-Mustaṣfā).
• Metaphysical and symbolic treatments of divine light (Mishkāt al-Anwār).
• Persian summaries and adaptations like Kīmiyā-yi Saʿādat.

Accounts of his death in 1111 often emphasize his piety and continued devotion to Sufi practices. Hagiographical sources describe him reciting the Qurʾan or engaging in worship shortly before dying; modern historians treat such details cautiously while acknowledging his enduring reputation as a scholar-saint in the Khurasani milieu.

7. Major Works and Literary Output

Al-Ghazālī’s corpus is extensive, covering theology, law, legal theory, ethics, Sufism, philosophy, and logic. Authorship of some treatises is debated, and precise dating remains uncertain in several cases, but a broad consensus identifies a core set of major works.

Overview of Principal Works

Questions of Authenticity and Chronology

Scholars note that:

• Some minor works attributed to al-Ghazālī may be by later authors capitalizing on his authority.
• The order of composition—especially of Tahāfut, Iḥyāʾ, and al-Munqidh—is reconstructed from internal evidence and remains partly contested.
• Certain texts (e.g., Mihakk al-Naẓar) have disputed authorship in part of the manuscript tradition.

Despite these uncertainties, most researchers agree that his output shows a developmental arc: from earlier legal and theological compendia, through intensive engagement with philosophy and logic, to a later, more explicitly Sufi-integrative phase where law, theology, and spiritual psychology are woven together.

8. The Iḥyāʾ and the Revival of Religious Sciences

Iḥyāʾ ʿUlūm al-Dīn (Revival of the Religious Sciences) is widely regarded as al-Ghazālī’s magnum opus, composed mainly during and after his period of withdrawal (late 1090s–early 1100s). It aims to reintegrate law, theology, and Sufism into a holistic program of religious life.

Structure and Content

The work is divided into four quarters, each encompassing ten “books”:

Al-Ghazālī blends ḥadīth, juridical discussion, ethical reflection, and Sufi anecdotes, often citing earlier ascetics and mystics.

Aims and Method

He presents the Iḥyāʾ as a response to what he saw as:

• Formalism among jurists, who focused on outward law while neglecting inner states.
• Excesses among some Sufis, who abandoned legal norms.
• Fragmentation of the religious sciences into specialized but spiritually disconnected disciplines.

His method includes:

• Reinterpreting ritual obligations as means of heart-purification.
• Systematizing tazkiyat al-nafs (purification of the soul) with quasi-psychological analyses.
• Integrating Sufi practices within a Sunni legal-theological framework.

Reception and Controversies

The Iḥyāʾ became enormously influential but also controversial:

• Supporters hailed it as a comprehensive “revival” of prophetic guidance, especially in the realm of ethics and spirituality.
• Some Ḥadīth scholars criticized its use of weak or fabricated reports.
• Certain legalists raised concerns about its Sufi-leaning discussions, such as on music (samāʿ) and ascetic practices.

Abridgments, commentaries, and adaptations—including the Persian Kīmiyā-yi Saʿādat—testify to its wide and enduring impact across regions and schools.

9. Critique of Philosophy in Tahāfut al-Falāsifa

Tahāfut al-Falāsifa (The Incoherence of the Philosophers), composed around 1095–1100, is al-Ghazālī’s most famous critique of Avicennian and Peripatetic philosophy. It targets primarily Ibn Sīnā (Avicenna) and, to a lesser extent, al-Fārābī.

Structure and Targets

The work is organized into twenty discussions addressing key philosophical doctrines in metaphysics, theology, and natural philosophy. Al-Ghazālī accuses the philosophers of inconsistency and overreliance on speculative reasoning.

He famously identifies three doctrines as crossing the boundary into unbelief (kufr):

On other points he accuses them of heresy or serious error, but not outright unbelief.

Methodological Approach

Al-Ghazālī employs a strategy of “immanent critique”: he accepts the philosophers’ premises for the sake of argument and attempts to show that their conclusions do not follow, or that alternative interpretations are equally rational. He makes extensive use of logical analysis while insisting on the primacy of revelation in matters beyond empirical or demonstrative proof.

His critique of necessary causality—arguing that what we perceive as causal connections are in fact habitual conjunctions established by God—is one of the work’s most discussed contributions and ties into his occasionalist metaphysics.

Later Responses and Interpretations

The Tahāfut provoked Ibn Rushd’s (Averroes) famous response, Tahāfut al-Tahāfut (Incoherence of the Incoherence), defending the philosophers. Subsequent Islamic thinkers debated:

• Whether al-Ghazālī’s aim was to destroy philosophy or to purge it of theological excesses.
• How deeply he remained influenced by Avicennian logic and psychology despite his criticisms.

Some modern scholars argue that, while he rejects specific metaphysical theses, he also contributes to the philosophization of kalām by adopting and reshaping philosophical tools within a theological framework.

10. Metaphysics: God, Creation, and Causality

Al-Ghazālī’s metaphysics centers on divine omnipotence, createdness of the world, and a distinctive doctrine of causality often labeled occasionalism.

God and Divine Attributes

Within an Ashʿarī framework, he affirms:

• God as the necessary being, utterly distinct from creation.
• Eternal attributes (knowledge, will, power, etc.) that are neither identical with the divine essence nor wholly separate substances.
• The impossibility of comprehending God’s essence, while acknowledging partial knowledge through revelation and reason.

He criticizes philosophical tendencies to reduce God to a purely abstract principle, emphasizing instead a personal, willing deity who freely creates and governs.

Creation and Eternity

Against Avicennian claims of the world’s eternity, al-Ghazālī maintains that:

• The world is temporally created ex nihilo by God’s free will.
• Arguments for eternity rely on assumptions about infinite series and necessity that he contests.
• Revelation clearly portrays creation as originating in time, which for him carries decisive weight where reason does not compel the contrary.

Some later interpreters explore whether he allowed for a notion of “ontological dependence” that could be expressed in quasi-eternalist terms, but mainstream readings hold that he insists on temporal beginning.

Causality and Occasionalism

His most distinctive metaphysical stance concerns cause and effect:

"

“There is no necessary connection between what is habitually associated, such that the existence of one would entail the existence of the other or its non-existence the non-existence of the other.”

— al-Ghazālī, Tahāfut al-Falāsifa

He argues that:

• Created things have no intrinsic causal efficacy.
• What we call “causes” are merely the occasions on which God habitually creates corresponding “effects”.
• The regularity of nature is due to God’s custom (ʿāda), not to necessary connections among created entities.

Proponents of this reading see him as a paradigmatic occasionalist. Some scholars nuance this by noting that he accepts stable patterns in nature for practical reasoning, even if metaphysically grounded in God’s will.

Hierarchy of Being and Light

In works like Mishkāt al-Anwār, he employs the metaphor of light (nūr) to describe degrees of reality and knowledge, with God as the “Light of the heavens and the earth”. This yields a semi-Neoplatonic hierarchy in which all beings receive existence and intelligibility from the divine light, while he nonetheless preserves a strict creator–creation distinction affirmed in kalām.

11. Epistemology: Doubt, Certainty, and Illumination

Al-Ghazālī’s epistemology is shaped by his personal crisis of doubt and his engagement with philosophical and theological methods.

Stages of Doubt and Critique of Sources

In al-Munqidh min al-Ḍalāl, he recounts subjecting different sources of knowledge to skepticism:

1. Sense perception: prone to illusion and error.
2. Intellectual reasoning: more reliable but still limited and potentially deceptive when extended beyond its domain.
3. Authority and tradition: valuable but insufficient without personal verification.

He extends his critique to the theologians, philosophers, Ismāʿīlīs, and eventually arrives at Sufism as offering a higher, experiential form of certainty.

Levels of Knowledge

Al-Ghazālī distinguishes between:

He does not discard rational inquiry; instead, he assigns it an important but limited role, especially in defending orthodoxy and organizing the sciences. Ultimate certainty, however, belongs to a suprarational mode.

Illumination and Divine Light

A central motif is knowledge as light:

"

“Certainty is a light that God casts into the heart; it is not obtained by proofs and arguments, but by a light that dawns in the heart when the veil is lifted.”

— al-Ghazālī, al-Munqidh min al-Ḍalāl

In Mishkāt al-Anwār and parts of the Iḥyāʾ, he presents an illuminationist account in which:

• The human heart (qalb) can become a mirror reflecting divine light.
• Purification and dhikr polish this mirror, allowing higher degrees of insight.
• Prophetic knowledge represents the highest form of illuminated understanding, combining revelation and direct vision.

Attitude to Logic and Demonstration

Despite his emphasis on illumination, al-Ghazālī is a strong proponent of formal logic. He argues in works like Miʿyār al-ʿIlm and al-Qisṭās al-Mustaqīm that:

• Logic is a neutral tool necessary for sound reasoning in theology and law.
• Demonstrative proofs (burhān) are valid within the created order, especially in mathematics and some natural phenomena.
• Attempts to extend demonstration to metaphysical and theological mysteries must be tempered by deference to revelation and the possibility of illumination.

Scholars differ on whether his epistemology represents a radical fideism or a sophisticated hierarchical integration of reason, revelation, and mystical experience.

12. Ethics, the Soul, and Spiritual Psychology

Al-Ghazālī develops a detailed spiritual psychology in which ethical transformation is inseparable from an understanding of the soul (nafs) and heart (qalb).

Anthropology: Heart, Soul, and Intellect

He uses overlapping terms to describe the human inner reality:

He draws on philosophical, kalām, and Sufi sources to portray the human being as a microcosm, with internal faculties mirroring cosmic and spiritual realities.

Vices and Virtues

In the Iḥyāʾ, especially the third and fourth quarters, he analyzes:

• Destructive traits (muhlikāt): pride, greed, envy, ostentation, anger, lust, love of the world.
• Saving traits (munjiyāt): repentance, patience, gratitude, trust in God, sincerity, love, and contentment.

His method combines:

• Diagnostic analysis of how a vice arises and manifests.
• Scriptural evidence for its dangers.
• Practical remedies, such as specific acts, reflections, and forms of ascetic discipline.

Purification and Character Formation

Ethical improvement is framed as tazkiyat al-nafs (purification of the soul). Al-Ghazālī holds that character traits (akhlāq) can be trained and transformed through:

1. Knowledge of the vice and its harms.
2. Opposite habitual actions (e.g., practicing generosity to counter miserliness).
3. Persistent dhikr and spiritual vigilance (murāqaba).

He rejects purely deterministic views of character, but acknowledges differences in temperaments and innate dispositions.

Teleology of the Ethical Life

The goal of ethical refinement is not merely social harmony or legal compliance, but proximity to God and preparation for the hereafter. Acts are evaluated not only outwardly but by intention (niyya):

"

“The purpose of knowledge is to act upon it; if one does not act, knowledge becomes a proof against him, not for him.”

— al-Ghazālī, Iḥyāʾ ʿUlūm al-Dīn

Ethics thus serves as the bridge between law, spiritual psychology, and metaphysical orientation. Scholars often regard his ethical writings as among the most influential expressions of a classical Islamic virtue ethics enriched by Sufi introspection.

13. Law, Legal Theory, and Theology

Al-Ghazālī was a prominent Shāfiʿī jurist and Ashʿarī theologian, and his contributions significantly shaped both uṣūl al-fiqh and kalām.

Jurisprudence and Legal Compendia

In positive law (fiqh), he authored texts such as al-Basīṭ, al-Wasīṭ, and al-Wajīz, which systematize Shāfiʿī rulings. These works vary in length and detail but share a methodical approach that helped standardize the school’s positions.

Legal Theory: al-Mustaṣfā and Beyond

His al-Mustaṣfā min ʿIlm al-Uṣūl is regarded as a classic in uṣūl al-fiqh. Key elements include:

• A refined classification of legal evidences: Qurʾan, Sunna, consensus (ijmāʿ), and analogy (qiyās).
• Use of logical terminology and structure, showing the influence of Avicennian logic.
• Discussion of maqāṣid (objectives) and maṣlaḥa (welfare) in a more subdued way than later theorists, but in ways that some see as anticipatory.

Scholars debate the extent to which he advanced a distinctively purposive approach versus consolidating earlier Ashʿarī-Shāfiʿī methods with clearer logical foundations.

Theology: Ashʿarī Kalām

In works like al-Iqtiṣād fī al-Iʿtiqād, al-Ghazālī presents what he calls a “moderate” creed, steering between extremes:

He critiques both Muʿtazilī rationalism and literalist tendencies, arguing for a balance between reason and scriptural submission.

Relations between Law, Theology, and Sufism

Although the detailed synthesis with Sufism is discussed elsewhere, within his legal-theological writings al-Ghazālī already insists on:

• The importance of intention in legal acts.
• The need for theologians and jurists to cultivate inner sincerity.
• A vision of law as serving the formation of the soul and the community’s salvation, not merely managing external conduct.

Later legal theorists across Sunni schools drew heavily on his uṣūl formulations, even when disagreeing with his Sufi leanings or occasionalist metaphysics.

14. Al-Ghazālī’s Sufi Synthesis

Al-Ghazālī is often credited with crafting a systematic “Sunnī Sufism” that integrates mystical practice with law and creed.

Sources and Influences

He draws on earlier Sufi authorities such as:

• al-Junayd, for sobriety and adherence to the law.
• al-Muḥāsibī, for introspection and spiritual accounting.
• Abū Ṭālib al-Makkī, whose Qūt al-Qulūb influenced sections of the Iḥyāʾ.

He combines these with Ashʿarī theology and elements of philosophical psychology, producing a relatively unified conceptual framework.

Integration with Law and Theology

Key aspects of his synthesis include:

He criticizes Sufis who ignore legal norms and jurists who dismiss spiritual disciplines, portraying both as partial and imbalanced.

Experiential Knowledge and Prophethood

Al-Ghazālī presents Sufi unveiling (kashf) as a continuation, at a lower level, of prophetic inspiration. While the law is complete and cannot be altered, individuals can attain degrees of inner understanding that:

• Illuminate the wisdom behind legal and ethical norms.
• Provide existential certainty about theological truths.

This position allows him to affirm post-prophetic mystical experience while protecting the finality of Muḥammad’s message.

Institutional and Historical Impact

His writings contributed to the mainstreaming of Sufism:

• Many later Sufi orders (e.g., Shādhilī, Naqshbandī) cited the Iḥyāʾ as a key manual.
• Madrasa curricula, especially in the eastern Islamic lands, incorporated parts of the Iḥyāʾ alongside law and theology.
• Some critics, particularly among Ḥanbalīs and strict literalists, remained wary of his emphasis on inner states and symbolic interpretations, but his model proved highly influential in shaping the normative image of Sufi piety in many Sunni contexts.

15. Reception, Criticism, and Influence in the Islamic World

Al-Ghazālī’s influence within the Islamic world has been extensive, but also contested, across regions, schools, and centuries.

Immediate and Medieval Reception

In the centuries after his death:

• Many Ashʿarī theologians and Shāfiʿī jurists embraced his works, especially the Iḥyāʾ and al-Mustaṣfā, incorporating them into teaching curricula.
• Sufi circles adopted the Iḥyāʾ as a foundational text for ethical and spiritual training.
• Some Ḥadīth scholars and Ḥanbalī theologians criticized his use of weak reports and his reliance on kalām and philosophical terminology.

Major Lines of Criticism

Prominent critics include:

Critics contended that al-Ghazālī:

• Excessively relied on kalām and philosophy, introducing speculative methods into religious discourse.
• Promoted Sufi ideas that, in their view, risked innovation (bidʿa) or doctrinal confusion.

Enduring Influence

Despite critiques, his works remained widely read:

• In Persia, Central Asia, and the Indian subcontinent, he became a standard reference for Sunni scholarship, influencing figures like al-Rāzī, al-Nawawī, and later Shāh Walī Allāh.
• In Ottoman and Mamluk contexts, commentaries and abridgments of the Iḥyāʾ, al-Mustaṣfā, and other works circulated among jurists, Sufis, and preachers.
• Some Shiʿi scholars engaged selectively with his ethical and mystical writings, sometimes adapting them within Imāmī frameworks.

Modern Muslim intellectuals have re-evaluated his legacy in light of contemporary concerns:

• Some laud him as a model for reconciling spirituality and rationality.
• Others argue that his critique of philosophy contributed to a decline in speculative sciences, though this causal link is debated.

Overall, his reception illustrates the plurality of Islamic intellectual traditions, in which the same figure can be revered as a saintly renewer, used as an authority in legal and educational contexts, and criticized as a problematic theologian or mystic.

16. Transmission to Latin Christendom and Jewish Thought

Al-Ghazālī’s influence extended beyond Islam through translations, adaptations, and polemical engagements in Latin Christian and Jewish intellectual traditions.

Latin Christendom

From the 12th century onward, several of his works, or texts attributed to him, were translated into Latin:

Notably, it was often his exposition of philosophy, rather than his critique in Tahāfut, that circulated. Consequently:

• Scholastics encountered “Algazel” as a philosopher of Avicennian type, rather than primarily as an opponent of philosophy.
• Thinkers such as Thomas Aquinas and Albert the Great cite “Algazel” among the philosophical authorities, sometimes siding with or refuting positions attributed to him.

Some modern historians argue that Latin reception partially misread al-Ghazālī, taking him as endorsing Avicennian doctrines he presented descriptively. Others suggest that even in this form he contributed to the dissemination of Islamic philosophical concepts in Christian Europe.

Jewish Philosophy

In Jewish thought, al-Ghazālī’s impact was both direct and indirect:

• Bāḥya ibn Paqūda’s earlier Duties of the Heart shares affinities with themes later elaborated by al-Ghazālī, and some scholars note convergences in ethical-introspective literature.
• Moses Maimonides was familiar with Islamic kalām and likely aware of al-Ghazālī’s works. Although he seldom mentions him by name, parallels exist in their critiques of theologians and their discussions of divine attributes and creation.
• Jewish kalām-influenced authors and later ethical writers sometimes drew on Arabic texts influenced by al-Ghazālī, adopting elements of his spiritual psychology and ethical categories.

There is debate over the extent of direct borrowing versus shared participation in broader Islamic intellectual milieus. Nonetheless, al-Ghazālī forms part of the background conversation that shaped key Jewish thinkers’ responses to philosophy and theology.

Overall, his presence in Latin and Jewish sources illustrates how Islamic thought functioned as a major interlocutor in medieval interreligious philosophy, even when his original intentions or emphases were transformed in the process of transmission.

17. Legacy and Historical Significance

Al-Ghazālī’s legacy is multifaceted, touching on theology, law, mysticism, ethics, and philosophy across many centuries.

Within Islamic Intellectual History

He is frequently described as:

• A “reviver” (mujaddid) of faith in his century, due to the integrative project of the Iḥyāʾ.
• A key architect of Sunnī orthodoxy, especially in Ashʿarī theology and Shāfiʿī legal theory.
• A principal figure in the institutionalization of Sufism within madrasa culture.

At the same time, some modern commentators argue that his criticism of falsafa contributed to a reorientation of intellectual energies away from speculative metaphysics and the natural sciences toward more theological and mystical pursuits. Others dispute any simple causal narrative, pointing to the continued vitality of philosophy and science in later Islamic contexts.

Cross-Cultural and Comparative Significance

Through Latin and, to a lesser extent, Hebrew receptions, al-Ghazālī became part of a shared medieval philosophical canon, influencing debates on:

• Metaphysics and theology (divine attributes, creation, eternity).
• Epistemology (limits of reason, role of revelation).
• Ethics and spiritual life.

Comparative philosophers and theologians have since drawn parallels between his thought and that of Augustine, Pascal, and various Christian mystics, while also highlighting crucial doctrinal differences.

Modern Reassessments

Contemporary scholarship and religious discourse variously present al-Ghazālī as:

These divergent evaluations underscore his continued relevance in discussions of faith and reason, law and spirituality, and the historical dynamics of Islamic thought.

While assessments of his ultimate impact vary, there is broad agreement that al-Ghazālī occupies a central place in the history of Islamic intellectual life and that understanding later developments in theology, Sufism, and legal theory is difficult without reference to his work.