Abū Bakr Aḥmad ibn Ḥusayn Ibn ‘Alī ibn Mūsa al-Khosrojerdi al-Bayhaqi (Arabic) , البيهقي also known as Imām al-Bayhaqi was born c. 994 CE/384 AH in the small town of Khosrowjerd near Sabzevar, then known as Bayhaq, in Khurasan.[8] During his lifetime, he became a famous Muslim hadith expert, following the Muslim ] school of Islamic Theology.