Ruhollah Khomeini was a lecturer at Najaf and Qom seminaries for decades before he was known on the political scene. He soon became a leading scholar of Shia Islam. He taught political philosophy, Islamic history and ethics. Several of his students – for example, Morteza Motahhari – later became leading Islamic philosophers and also "marja"'. As a scholar and teacher, Khomeini produced numerous writings on Islamic philosophy, law, and ethics. He showed an exceptional interest in subjects like philosophy and mysticism that not only were usually absent from the curriculum of seminaries but were often an object of hostility and suspicion.