Yassine was born in Marrakesh. He worked as a teacher and a school inspector for the Ministry of Education, and from 1965 on, was a member of one of the most famous Moroccan Sufi brotherhoods, the Boutchichiyya. Yassine reportedly fell out with the leadership of the brotherhood over its refusal to engage more directly in political matters, and founded his own organisation. Yassine was jailed in a mental asylum for three years for publishing an open letter to King Hassan II denouncing his rule as unIslamic. Following his release he was kept under house arrest for many years, before eventually being released in the early years of the rule of King Mohammed VI. Yassine's many publications include L'Islam ou le Deluge (Islam or the Flood), probably the best known of his works. He died, aged 84, on 13 December 2012.