He became a devout Muslim, and went to study the Koran in Egypt where he formed the belief that Palestine was an Islamic land "consecrated for future Muslim generations until Judgment Day" - and that no Arab leader had the right to give any of it up. Sheikh Yassin's message was simple, and one from which he never wavered: "I just want my house back." He did not come to prominence until the first Palestinian intifada of 1987, when he launched the Islamic Resistance Movement, whose acronym, Hamas, means "zeal".