Q 216: What is the proof that `Uthman (May Allah be pleased with him) has the right to the Caliphate and being a successor to Abu Bakr and `Umar?
A--- Narrated `A'ishah (May Allah be pleased with her) Allah's Messenger (Peace be upon him) saying: "O 'Uthman! /fone day Allah gave you this issue (the Caliphate) and the hypocrites wanted you to take off the shirt (Caliphate) Allah bestowed on you, do not take it off" He said it thrice.
(Ibn Majah, At- Tirmidhi, Ibn Hibban and AI-Hakim)
The People of Shura (Consultation) agreed on him, then all the Prophet's companions. The first to pay him homage was `Ali Ibn Abu Talib after 'Abdur-Rahman Ibn 'Auf, then the rest of the people.
Reference: 200 FAQ On Muslims Belief - Shiekh Hafiz Ibn Ahmed Al Hakami