Al Bahrani wrote on Twelver doctrine, affirmed free will, the infallibility of prophets and imams, the appointed imamate of `Ali, and the occultation of the Twelfth Imam. Yusuf al-Bahrani Yusuf ibn Ahmed al-Bahrani (1695–1772) (Arabic: يوسف البحراني) was a Bahraini theologian and a dominant person in the intellectual development of Twelver Shia Islam. Isa Qassim Ayatollah Sheikh Isa Ahmed Qassim (Arabic: آية الله الشيخ عيسى أحمد قاسم) is Bahrain's leading Shia cleric and a politician. He is the spiritual leader of Al Wefaq, Bahrain's biggest opposition society. He was the leader and the founders of Islamic Enlightenment institution.