Ahmad ibn al-Husayn ibn `Ali ibn `Abd Allah ibn Musa, Abu Bakr al-Bayhaqi al-Naysaburi al-Khusrawjirdi al-Shafi`i al-Ash`ari , “the jurisprudent imam, hadith master. one of the mountains of Islamic knowledge.”

He took fiqh from the imam Abu al-Fath Nasir ibn al-Husayn ibn Muhammad al-Qurashi al-`Umari al-Marwazi al-Shafi`i al-Naysaburi among others.

Al-Bayhaqi lived frugally in the manner of the pious scholars. He began fasting perpetually thirty years before his death.Al-Bayhaqi is the last of those who comprehensively compiled the textual evidence of the Shafi`i school including the hadith, the positions of the Imam and his immediate companions.

Al-Bayhaqi belongs to the the third generation of Imam Abu al-Hasan al-Ash`ari’s students and took kalam from the two Ash`ari imams Ibn Furak and Abu Mansur al-Baghdadi.