What is the reason for the angels' modesty towards Uthman, may Allah be pleased with him, and what did he do to attain this status?

Uthman (may Allah be pleased with him) was among the best of people in character and the most modest. The Messenger of Allah (peace be upon him) described him as "the most truthful of them in modesty," and that the angels were shy of him, due to the greatness of the characteristic of modesty within him. This is evidenced by the hadith narrated by Aisha (may Allah be pleased with her), that the Prophet (peace be upon him) straightened his clothes when Uthman sought permission to enter, and said: "Should I not be shy of a man whom the angels are shy of?" Uthman was even shy of himself when he was alone.