Abū Ḥāmid Muḥammad al-Ghazālī is perhaps, after the Prophet and the Companions, the most influential Muslim thinker in history. Named Ḥujjat al-Islām · حُجَّة الإِسْلَام — “the Proof of Islam” — he accomplished, alone, what none would have imagined possible: to bring Sufism into the heart of Sunni orthodoxy, against the juridical currents that saw in it a deviance.
The prodigy of Ṭūs
He was born into a humble family of Ṭūs, in Persian Khorasan, in 1058. Orphaned young, he was raised with his brother Aḥmad by a Sufi friend of his father. He studied first in Ṭūs, then in Jurjān, and finally in Nishapur, where he became the disciple of one of the greatest Ashʿarī theologians of the time, al-Juwaynī. At the death of the master in 1085, the young Ghazālī — he was twenty-seven — was noticed by the great Seljuk vizier Niẓām al-Mulk, who appointed him principal professor at the Niẓāmiyya of Baghdad — the most prestigious university of the Muslim world.
For four years (1091-1095), Ghazālī was at the summit of the Sunni intellectual world. He taught before three hundred disciples. He brilliantly refuted the philosophical doctrines of Greek inspiration (falsafa) in his Tahāfut al-Falāsifa (“Incoherence of the Philosophers”), which would have an enormous resonance. He composed treatises of law, of theology, of logic. He frequented the princes. He had everything — glory, knowledge, wealth.
The crisis — 1095
And in July 1095, at thirty-seven, abruptly, everything collapsed. It is he himself who, later, would recount the crisis in his spiritual autobiography, the Munqidh min al-Ḍalāl (“The Deliverer from Error”):
Considering attentively my occupations — of which the best was no more than teaching — I saw that I was pursuing sciences without importance, unworthy of the journey of the hereafter. When I probed the intention of my teaching, I discovered that it was not pure for the face of God, but that its cause and its motive were the search for renown and glory. Al-Ghazālī, Al-Munqidh min al-Ḍalāl
This awareness became a physical sickness: he lost his voice, could no longer teach, could no longer swallow. The physicians declared the origin psychic. In the month of Dhū l-Qaʿda 488 H. (November 1095), he abandoned everything — his chair, his rank, his fortune (which he distributed to his family, keeping the strict minimum), and he took to the road. Under the pretext of pilgrimage to Mecca, he left Baghdad never to return.
The ten years of the desert
There would follow eleven years of wandering and retreat (1095-1106). He passed through Damascus, where he lived in a chamber of the minaret of the great Umayyad mosque — meditating, fasting, performing the khalwa. Then Jerusalem, where he withdrew into the dome of the Rock. Then Mecca and Medina for the pilgrimage. Then a return toward Egypt. Throughout this time, he practised with rigour the Sufi disciplines — continual invocation, retreat, spiritual listening, examination of conscience.
At the end of these years, he had changed. The combative theologian, the cutting mind that wielded syllogisms, had become a man of the heart. He discovered what he would call dhawq · ذَوْق — spiritual savour, tasting. A knowledge that passes neither through words nor through reasonings, but that is tasted directly.
I knew then with certainty that the Sufis are on the way of God, and that this way is the best;
their character is the purest that can be found…
He who does not know spirituality through tasting (dhawq) perceives of the reality of prophecy only the name. Al-Ghazālī, Al-Munqidh min al-Ḍalāl
The work of maturity
From 1106, Ghazālī returned to teaching — but transformed. He taught in Nishapur, then in Ṭūs, in very different conditions: no more great chairs, no more audiences of princes. He wrote, above all. His late work is one of the most powerful in the history of Islam.
Iḥyāʾ ʿulūm al-dīn — The Revival of the Religious Sciences
Forty books in four volumes — the masterly work that has crossed the centuries. Ghazālī takes up the whole matter of religion (rites, human transactions, vices to combat, virtues to acquire, the spiritual way) and reinterprets it in the light of Sufism. Each rite receives its inner meaning, each virtue its metaphysical foundation, each devotion its contemplative dimension. It is the work that, more than any other, has enabled pious Muslims to enter the Sufi way without rupture with common practice.
Al-Munqidh min al-Ḍalāl — The Deliverer from Error
A brief spiritual autobiography in which Ghazālī retraces his itinerary — the examination of the four ways of knowledge (theology, philosophy, Bāṭinī esotericism, Sufism), the crisis, the conversion, the return. A text unique in Islamic literature: a personal testimony that recalls the Confessions of Augustine.
Mishkāt al-Anwār — The Niche of Lights
A mystical commentary on the famous Verse of Light (Quran 24:35). Ghazālī unfolds there a metaphysics of light that announces Suhrawardī al-Maqtūl and the Iranian Illuminationist school. One of his most profound texts, and one of the most contested by the literalists.
In all, nearly seventy works — law, theology, anti-philosophical and anti-Ismaili polemic, Sufism, exegesis, education. All traversed by the same conviction: religion cannot be exhausted in outward practice, it requires interiorisation.
The osmosis between orthodoxy and Sufism
What Ghazālī accomplished, his century would see only by half. But with time, it became an evidence: after him, Sufism is no longer suspect of heresy among the Sunnis. It becomes, on the contrary, the very soul of Sunnism. All the great classical Sufi orders would attach themselves to him in one way or another. The contemporary shaykh of al-Azhar who declares himself a Sufi traces his lineage back through Ghazālī.
How did he accomplish this? By showing that the Sufi way invents nothing — it revives. It does not replace the prescribed prayer, it inhabits it. It does not dispense with Islamic law, it interiorises it. It does not reject theology, it surpasses it toward tasting. The Iḥyāʾ is the practical manual of this synthesis — and it is read, even today, in the madrasas of Morocco, Yemen, Malaysia.
A universal influence
Ghazālī has also been read outside Islam. In the thirteenth century, his works were translated into Latin by Dominicus Gundissalinus in Toledo. Thomas Aquinas cites him. Later, some think Pascal heard of him through the Jansenists interested in the Sufis; Schopenhauer mentions him. He is one of the very few Muslim spiritual writers whose reading spread through the medieval Christian world.
In the twentieth century, Massignon, Gardet, Watt, then Nasr and Geoffroy made his work known to the French-speaking and English-speaking public. The Iḥyāʾ is today partially translated into more than twenty languages.
The return to Ṭūs
Ghazālī died in 1111, in Ṭūs, his native town. According to one tradition, a poem was found on his bedside table, written the night of his death:
I am a bird: this body was my cage,
But I have flown away, leaving it as a sign. Al-Ghazālī, last poem
The combative theologian who once feared God as a severe judge died as a Sufi who takes flight toward the Beloved. The path was long. It would allow millions of Muslims, after him, to walk more easily.