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.
"When a person dies, his works end, except for three: ongoing charity, knowledge that is benefited from, and a righteous child who prays for him."
Prophet Mohammed (PBUH)
"The best of what a man leaves behind are three: a righteous child who supplicates for him, ongoing charity the reward of which reaches him, and knowledge that is acted upon after him."
Sunan Ibn Mājah
"Every day two angels come down from Heaven and one of them says, 'O Allah! Compensate every person who spends in Your Cause,' and the other (angel) says, 'O Allah! Destroy every miser.'"
Sahih Bukhari