Morteza, son of Mohammad Amin Shushtari Dezfuli, known as Sheikh Ansari, was born in 1799 in Dezful. He descended from the pure lineage of one of the descendants of Jabir ibn Abdullah Ansari, a renowned companion of the Prophet Muhammad (peace be upon him and his family).
Sheikh Morteza Ansari is considered one of the most prominent jurists and scholars of the 13th century AH. He is regarded as one of the founders of modern principles in Ja'fari jurisprudence and its legal theory. His legacy is immortalized through his two timeless works, Al-Makasib and Rasa'il, which have firmly established his name in the realm of authentic Islamic knowledge.