الغَزَالِيّ — حُجَّةُ الإِسلَامِ وَمُؤَلِّفُ إِحيَاءِ عُلُومِ الدِّينِ وَتَهَافُتِ الفَلَاسِفَة: العَالِمُ الَّذِي قَادَتهُ أَزمَتُهُ الإِيمَانِيَّةُ الشَّخصِيَّةُ إِلَى تَركِيبٍ لِلفِقهِ الإِسلَامِيِّ وَعِلمِ الكَلَامِ وَالتَّصَوُّفِ أَعَادَ تَعرِيفَ مَعنَى الإِسلَامِ السُّنِّيِّ الأُرثُوذُكسِيّ
Al-Ghazali (الغَزَالِيّ; full name: Abu Hamid Muhammad ibn Muhammad al-Ghazali al-Tusi; born 450 AH / 1058 CE in Tus, Khorasan [modern Iran]; died 505 AH / 1111 CE in Tus; title: Hujjat al-Islam [Proof of Islam]; the trajectory: studied under al-Juwayni [Imam al-Haramayn] in Nishapur; appointed by Nizam al-Mulk [the Seljuk vizier] to teach at the Nizamiyya madrasa in Baghdad; at the height of his fame at ~37, al-Ghazali fell into a crisis of faith — a period of doubt about the certainty of his own knowledge; resigned from the Nizamiyya [1095 CE]; spent ~11 years as a wandering Sufi in Syria, Palestine, and the Hijaz; returned to teaching; the crisis: described in al-Munqidh min al-Dalal [Deliverance from Error]: al-Ghazali doubted whether he could be certain of anything; Cartesian-style skeptical regress; recovered through what he describes as a light God cast into his heart; major works: [1] Ihya 'Ulum al-Din [Revival of the Religious Sciences]: the magnum opus; 4 volumes: 'ibadat [worship], 'adat [customs and social life], muhlikat [destructive moral traits], munjiyat [saving moral traits]; the project: Islamic law tells you WHAT to do; the Ihya teaches you HOW to do it sincerely, with the heart's presence; the synthesis: Sufi spiritual psychology + Shafi'i fiqh + Ash'ari theology; Ibn Rushd [Averroes] wrote an entire response [Tahafut al-Tahafut] defending the philosophers; [2] Tahafut al-Falasifa [Incoherence of the Philosophers]: attacked 17 philosophical positions as wrong and 3 as heretical: [a] eternity of the world [God created the world in time; the philosophers say it is eternal]; [b] God's knowledge [the philosophers say God knows only universals, not particulars]; [c] bodily resurrection [the philosophers deny this]; the accusation of kufr [unbelief] against philosophers who held these three positions was enormously consequential; [3] Fada'ih al-Batiniyya [Scandals of the Esotericists]: direct attack on the Ismaili ta'wil tradition; argues the Batiniyya [Ismailis] use ta'wil to undermine the shariah by making the zahir optional; [4] Al-Mustasfa [The Pure Source]: fiqh usul treatise, still taught in Islamic law curricula; [5] Al-Munqidh min al-Dalal [Deliverance from Error]: spiritual autobiography; [6] Maqasid al-Falasifa [Aims of the Philosophers]: summary of Avicennan philosophy [before the Tahafut critique]; Sufism: al-Ghazali's personal resolution of the epistemological crisis was Sufi: he concluded that genuine certainty comes only through direct spiritual experience [dhawq: tasting], not through rational demonstration or textual authority alone; but he insisted this Sufi realization must be grounded in the sharia's zahir — not escape from it; legacy: one of the most influential Muslim scholars in history; 'had there been a prophet after Muhammad, it would have been al-Ghazali' [said by later scholars in appreciation, not doctrine]; his synthesis of sharia, kalam, and tasawwuf set the template for classical Sunni orthodoxy for centuries; his attack on Ismaili ta'wil was taken seriously enough to generate extensive Ismaili responses) is the central figure of classical Sunni synthesis.
A Crisis That Shaped Islamic Thought
In 1095 CE, at the height of his fame as professor at Baghdad’s premier madrasa, Abu Hamid al-Ghazali collapsed into an epistemological crisis. He could not speak; he couldn’t teach. He resigned his position and spent eleven years wandering — Syria, Palestine, the Hijaz — as a Sufi.
The crisis, described in Al-Munqidh min al-Dalal (Deliverance from Error), was Cartesian in structure: al-Ghazali found himself unable to ground his knowledge claims in anything certain. Sense perception deceives; rational demonstration rests on unproven axioms. He eventually emerged through what he describes as “a light God cast into his heart” — not an argument but an experience.
The Ihya: Revival Without Abandonment
Ihya ‘Ulum al-Din (Revival of the Religious Sciences) is the most ambitious work of Islamic synthesis ever attempted. Its four volumes move through worship, social life, destructive character traits, and saving character traits — covering the full range of Muslim life.
The project’s insight: Islamic law (fiqh) specifies the outward form of every action, but it does not guarantee the inner sincerity that makes the action spiritually effective. The Ihya is the manual for doing the zahir correctly (Shafi’i fiqh) while simultaneously cultivating the batin (Sufi spiritual psychology). The framework is Ash’ari; the depth is Sufi; the law is Shafi’i.
Tahafut and the Attack on Philosophy
Tahafut al-Falasifa (Incoherence of the Philosophers) dismantled seventeen Avicennan positions as mistaken and declared three positions heretical: the eternity of the world, God’s non-particular knowledge, and denial of bodily resurrection. The charge of kufr against the philosophers had enormous consequences — it cast suspicion over philosophical inquiry in the Islamic world for centuries.
See also: Seerah Al Mawardi, Seerah Ibn Al Qayyim, Seerah Sufyan Ibn Uyayna, Ismaili Tawil Of Al Tanzil Wal Tawil, Fiqh Al Usul Al Fiqh