Mansour al-Hallaj (Arabic: ابو المغيث الحسين بن منصور الحلاج, romanized: Abū 'l-Muġīth al-Ḥusayn ibn Manṣūr al-Ḥallāj) or Mansour Hallaj (Persian: منصور حلاج, romanized: Mansūr-e Hallāj) (c. 858 – 26 March 922) (Hijri c. 244 AH – 309 AH) was a Persian mystic, poet, and teacher of Sufism.

[5][6][7] He is best known for his saying, "I am the Truth" ("Ana'l-Ḥaqq"), which many saw as a claim to divinity, while others interpreted it as an instance of annihilation of the ego, allowing God to speak through him.

Al-Hallaj gained a wide following as a preacher before he became implicated in power struggles of the Abbasid court and was executed after a long period of confinement on religious and political charges.

[3][4] When he was twenty, al-Hallaj moved to Basra, where he married and received his Sufi habit from 'Amr Makkī, although his lifelong and monogamous marriage later provoked jealousy and opposition from the latter.

[9] At that time a number of Sunnis, including former Christians who would later become viziers at the Abbasid court, became his disciples, but other Sufis were scandalized, while some Muʿtazilis and Shias who held high posts in the government accused him of deception and incited the mob against him.

[9] Al-Hallaj left for eastern Iran and remained there for five years, preaching in the Arab colonies and fortified monasteries that housed volunteer fighters in the jihad, after which he was able to return and install his family in Baghdad.

[9] Al-Hallaj made his second pilgrimage to Mecca with four hundred disciples, where some Sufis, his former friends, accused him of sorcery and making a pact with the jinn.

[9] After returning to his family in Baghdad, al-Hallaj began making proclamations that aroused popular emotion and caused anxiety among the educated classes.

[7] Witnesses reported that al-Hallaj's last words under torture were "all that matters for the ecstatic is that the Unique should reduce him to Unity", after which he recited the Quranic verse 42:18.

[18] Sadakat Kadri points out that "it was far from conventional to punish heresy in the tenth century," and it is thought he would have been spared execution except that the vizier of caliph al-Muqtadir wished to discredit "certain figures who had associated themselves" with al-Hallaj.

[19] (Previously al-Hallaj had been punished for talking about being at one with God by being shaved, pilloried and beaten with the flat of a sword, not executed because the Shafi'ite judge had ruled that his words were not "proof of disbelief.

He was said to have "lit four hundred oil lamps in Jerusalem's Church of the Holy Sepulchre with his finger and extinguished an eternal flame in a Zoroastrian fire temple with the tug of a sleeve.

[21] Hallaj was also accused of ḥulūl "incarnationism", the basis of which charge seems to be a disputed verse in which the author proclaims mystical union in terms of two spirits in one body.

While meditating, he uttered انا الحق The earliest report, coming from a hostile account of Basra grammarians, states that he said it in the mosque of al-Mansur, while testimonies that emerged decades later claimed that it was said in private during consultations with Junayd Baghdadi.

In the 11th volume of the proto-Salafist Ibn Kathir's book al-Bidaya wa-l-Nihaya, it is said that al-Hallaj used to deceive people by putting on plays with his hired men under the guise of spiritual healing, and extorting money from them by cunning and secret, and it is also stated that, he came to India to learn and practice Indian magic.

[7] Ṭawāsīn is the broken plural of the word ṭā-sīn which spells out the letters ṭā (ط) and sīn (س) placed for unknown reasons at the start of some surahs in the Quran.

[29] In virtually every major current of juridical and theological thought (Hanafi, Maliki, Shafi'i Hanbali, Maturidi, Ash'ari, and also Shia Jafari) one finds his detractors and others who accepted his legacy completely or justified his statements with some excuse.

[18] Some Sufi authors claimed that such utterances were misquotations or attributed them to immaturity, madness or intoxication, while others regarded them as authentic expressions of spiritual states, even profoundest experience of divine realities, which should not be manifested to the unworthy.

[31] Malayalam author Vaikom Muhammad Basheer draws parallel between "Anā al-Ḥaqq" and Aham Brahmasmi, the Upanishad Mahāvākya which means 'I am Brahman' (the Ultimate Reality in Hinduism).

There was a belief among European historians that al-Hallaj was secretly a Christian, until the French scholar Louis Massignon presented his legacy in the context of Islamic mysticism in his four-volume work La Passion de Husayn ibn Mansûr Hallâj.