Abu al-Qasim al-Ansari

al-Anṣārī, Abū l-Qāsim Salmān b. Nāṣir b. 'Imrān al-Arghiyānī al-Nīsābūrī al-Ṣūfī al-Shāfi'ī (Arabic: أبو القاسم الأنصاري), commonly known as Abu al-Qasim al-Ansari, was a Persian Sunni scholar known for being an Ash'arite theologian, Shafi'i jurist, traditionist, scriptural exegete and mystic during the Islamic Golden Age. He was the famous pupil of Imam al-Haramayn al-Juwayni and greatly influenced by him, as can be seen by his own theological writings. He was referred to as Sayf al-Nazr (Arabic: سيف النظر, lit. '"Sword of insight"').

As a Muslim scholar of the Sunni branch and Shafi'i school, his studies covered the fields of Islamic theology, Usul al-Din (principles of faith), Shafi'i jurisprudence, Sufism, Interpretation of Quran, and the studies of Hadith. Among his most prominent students were Al-Shahrastani, the author of Al-Milal wa al-Nihal, and Ibn al-Sam'ani, the author of Kitab al-Ansab. He lived under the Abbasid Caliphate, between the second half of the fifth century AH and beginning of the sixth century AH of the Islamic calendar.