The doctrinal basis of the Guardianship of the Islamic Jurist comes at least in part from the hadith where Islamic Prophet Muhammad is reputed to have said "The ulama are the inheritors of the prophets" (). The issue was mentioned by the earliest Shi'i mujtahids such as al-Shaykh Al-Mufid (948–1022), and enforced for a while by Muhaqqiq Karaki during the era of Tahmasp I (1524–1576). However, according to John Esposito in "The Oxford Dictionary of Islam", Morteza Ansari (~1781–1864) was the first Islamic scholar to advance the theory of the Guardianship of the Islamic Jurist.