Because of his conversion to Islam, Uthman had to face another crisis. His wives refused to accept Islam, and Uthman separated himself from his wives. That was a matter of great grief for Uthman, but so great was his love for Islam that he felt no sacrifice too great in the cause of Islam. He felt distressed at the break up of his family life, but Islam was certainly more valuable for him.
The Holy Prophet of Islam was much impressed with the sacrifice that Uthman had made in the cause of Islam, and he married his second daughter Ruqayya to Uthman. In the days of ignorance Ruqayya had been engaged to her cousin Utba son of Abu Lahb, an uncle of the Holy Prophet. When the Holy Prophet declared his mission Abu Lahb became hostile to him, and under his instructions Utba repudiated his engagement to the daughter of the Holy Prophet. Uthman and Ruqayya made a unique pair. Uthman was the most beautiful person among men, and Ruqayya was the most beautiful person among the women of Makkah.
On the marriage of Uthman and Ruqayya, Saadi the maternal aunt of Uthman composed some verses. She said:
"Uthman the noble souled became a Muslim; And Muhammad the Prophet of Islam married him to his daughter; Thus, the moon and the sun were united; O son of Banu Hashim, to you I pay my tribute; You are undoubtedly the Messenger of Allah, Sent for the guidance of mankind".
In his book History of the Caliphs, Jalaluddin Suynti tells an anecdote highlighting the comeliness of the Uthman-Ruqayya pair. It is related that one day the Apostle of God sent Usama b Zaid to the house of Uthman with a dish of meat. Usama was then a child of six or seven years. He says that some time he looked at Ruqayya and some time at Uthman, and wondered at their beauty. Usama relates that on return from the house of Uthman, the Holy Prophet asked him, "Have you ever seen a more comely pair than Uthman and Ruqayya"? Usama said "Never, O Apostle of Cod".