Conservative opposition arose to Muhammad's speeches. According to Ibn Sad, the opposition in Mecca started when Muhammad delivered verses that "spoke shamefully of the idols they (the Meccans) worshiped other than Himself (God) and mentioned the perdition of their fathers who died in disbelief. As the ranks of Muhammad's followers swelled, he became a threat to the local tribes and the rulers of the city, whose wealth rested upon the Kaaba, the focal point of Meccan religious life, which Muhammad threatened to overthrow