Uthman had very close and intimate friendly relations with Abu Bakr. It was, as a matter of fact, at the instance of Abu Bakr that Uthman had accepted Islam. Accordingly when Abu Bakr was elected as the Caliph, Uthman was the first person after Umar to offer allegiance to Abu Bakr. Uthman served in the contingent that was sent by Abu Bakr to Syria under the command of Usama. During the apostasy wars, Uthman remained at Madina to act as Abu Bakr's Adviser.
On his death bed Abu Bakr dictated his will about his successor to Uthman. Abu Bakr dictated in order to avoid the conflict among the Muslims in the matter of his successor, he proposed to make the nomination himself. Thereafter Abu Bakr fell into a swoon, and Uthman wrote of his own accord that the person to be nominated as his successor was to be Umar. When Abu Bakr recovered from the swoon he wanted Uthman to read what he had written. Uthman read the passage including the nomination of Umar. Abu Bakr praised Uthman for his foresight in reading what was in the mind of Abu Bakr. Abu Bakr held that fearing that he (Abu Bakr) might not recover from the swoon, Uthman did the right thing in inserting the name of Umar for that was indeed his intention. After the death of Abu Bakr, Uthman was the first person to offer allegiance to Umar
"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