Abu al-Mu'in al-Nasafi

Abu al-Mu'in al-Nasafi (full name Maymun ibn Muhammad al-Nasafi al-Makhuli) was a theologian of Transoxiana — the region beyond the Oxus River in Central Asia — and the most influential systematizer of the Maturidi school of Sunni kalam (speculative theology) after its founder, Abu Mansur al-Maturidi. Sources record his birth in Nasaf (present-day Qarshi, Uzbekistan), though they disagree on the year, giving either 418 AH (1027 CE) or 438 AH (1046 CE). He died in 508 AH (1114-15 CE), and his grave is reported near Qarshi.

He came from a scholarly family: tradition holds that his ancestor Makhul al-Nasafi was a disciple of al-Maturidi himself, anchoring him in the school's lineage. His major work, the two-volume Tabsirat al-adilla ("Clarification of the Proofs"), is widely regarded as the second most important Maturidi text after al-Maturidi's own Kitab al-Tawhid; it is more systematically organized and more accessible than its predecessor, earning him the epithet "Sahib al-Tabsira" (Author of the Tabsira). He also wrote the shorter Bahr al-kalam and al-Tamhid.

Modern scholars sometimes call him a "second founder" of Maturidism, comparing his role to that of al-Baqillani among the rival Ash'aris. His formulations were closely followed by Najm al-Din Umar al-Nasafi, author of the famous creed al-Aqa'id al-Nasafiyya — a different, later scholar with whom he should not be confused.