| Religion: | Islam |
| Occupation: | Theologian, Scholar, Jurist, Legal theoretician, Grammarian, Heresiologist, Mathematician |
| Era: | Islamic golden age |
| Abū Manṣūr al-Baghdādī (Arabic: أَبُو مَنْصُورالبغدادي) | |
| Imam | |
| Birth Date: | 980 |
| Birth Place: | Baghdad |
| Death Date: | 1037 (429 AH) (aged 56–57) |
| Death Place: | Isfayayin |
| Region: | Khorasan |
| Denomination: | Sunni |
| Jurisprudence: | Shafi'i |
| Creed: | Ash'ari[1] [2] |
| Main Interests: | Theology (Kalam), Islamic Jurisprudence, Principles of Islamic jurisprudence, Arabic grammar, Mathematic |
| Notable Works: | Al-Farq bayn al-Firaq Kitab Uṣul al-Din |
| Influences: | Al-Shafi'i Abu Hasan al-Ash'ari Abu Ishaq al-Isfarayini |
| Influenced: | Al-Qushayri Al-Bayhaqi |
Abū Manṣūr ʿAbd al-Qāhir ibn Ṭāhir bin Muḥammad bin ʿAbd Allāh al-Tamīmī al-Shāfiʿī al-Baghdādī (Arabic: أبو منصور عبدالقاهر ابن طاهر بن محمد بن عبدالله التميمي الشافعي البغدادي), more commonly known as Abd al-Qāhir al-Baghdādī (Arabic: عبد القاهر البغدادي) or simply Abū Manṣūr al-Baghdādī (Arabic: أَبُو مَنْصُورالبغدادي) was an Arab[3] Sunni scholar from Baghdad. He was considered a leading Ash'arite theologian and Shafi'i jurist. He was an accomplished legal theoretician, man of letters, poet, prosodist, grammarian, heresiologist and mathematician.
'Abd al-Qahir al-Baghdadi was born and raised in Baghdad.[4] He was a member of the Arab tribe of Banu Tamim.[3] Ibn 'Asakir writes that Abu Mansur met the students of the companions of Imam al-Ashari and acquired knowledge from them.[5] Among the Ashari imams of the third generation, he is the senior of al-Bayhaqi and the identical contemporary of Abu Dharr al-Harawi and Abu Muhammad al-Juwayni. Abu Mansur was brought in his youth by his father from Baghdad to Nishapur. In his new city is where he found his education. Abu Mansur was known as a wealthy man where he donated his whole fortune to the scholars of wisdom until he was qualified to instruct in seventeen various subjects, including fiqh, usul, arithmetic, law of inheritance and theology. Most of the scholars of Khurasan were his pupils. He was a senior pupil of Abu Ishaq al-Isfarayini, and he and Abu Sahl al-Su'luki steadfastly upheld the al-Shafi`i view that "the Book cannot be abrogated by the Sunna." In the mosque of `Aqil, Abu Mansur took over as headmaster from Abu Ishaq al-Isfarayini, and it was under his tutelage that al-Bayhaqi, al-Qushayri, Abu Khalaf al-Tabari, and Nasir al-Marwazi learned. He studied Hadith under Abu Bakr al-Isma'ili and others. Due to Turkmen riots near the end of his life, Abu Mansur was forced to flee from Nishapur and established himself as a venerable citizen of Isfayayin, where he passed away in 449/1038. He was buried right next to his teacher Abu Ishaq al-Isfarayini.
Abu Uthman al-Sabuni highly praised him and said: “one of the imams of the principles of the Religion and foremost authorities of Islam by consensus of its most eminent and competent scholars.”
'Abd al-Qahir al-Baghdadi was a prolific writer who wrote on numerous subjects and authored several quality books including Kitāb Uṣūl al-Dīn, a systematic treatise, beginning with the nature of knowledge, creation, how the Creator is known, His attributes, etc.... and Al-Farq bayn al-Firaq which takes each sect separately, judges all from the standpoint of orthodoxy and condemns all which deviate from the straight path. Both books were major works on the beliefs of Ahl al-Sunna.[4] His other following known works include: