Abu Bakr Ahmad ibn al-Husain ibn Ali ibn Abdullah ibn Mosa al-Baihaqi was born in Sha’baan in 384 H. in Khusrujird. He died at the age of 74 years in 458 H. in Nishapur and was buried in Baihaq. He wrote many famous books e.g. "as-Sunan al-Kubra," "Ma’rifat as-Sunan wal Aathaar," "Dalaa’il an-Nubuwwaah" and "Ma’rifat Ahwaal Sahib ash-Sharee’ah".