Uthman was a great Muslim. He followed the injunctions of Islam rigorously in letter as well as in spirit. He spent a greater part of the night in prayers. He knew the Holy Quran by heart, and would complete the recitation of the whole of the Holy Quran during a night. He held that the primary and basic responsibility of the Caliph was to protect and safeguard Islam, and take steps to promote its purposes and values. During his caliphate Uthman took several measures with a view to promoting the purposes of Islam.