Glad tidings of martyrdom to Hadhrat ‘Uthman
The Holy Prophet (Sallallahu alaihi wa sallam) is aware of the events and conditions of every follower of His. This is the reason why He (Sallallahu alaihi wa sallam) gave glad tidings of martyrdom to Hadhrat ‘Uthman (May Allah be well pleased with him). There is a Hadith in Sahih Bukhari:
Translation: It has been narrated on the authority of Hadhrat Anas Bin Malik (May Allah be well pleased with him), he said that the Holy Prophet (Sallallahu alaihi wa sallam) graced the mountain of Uhud along with Hadhrat Abu Bakr Siddiq, Hadhrat Umar Farooq and Hadhrat Uthman (May Allah be well pleased with them). The mountain of Uhud started swaying out of happiness. The Holy Prophet (Sallallahu alaihi wa sallam) tapped it with His foot and said: Steady o mountain! The Prophet is on you and 1 faithful (Siddiq) and 2 martyrs (Shaheed). (Sahih Bukhari, Hadith No: 3686)
Imam Jalaluddin Suyuti (May Allah shower His mercy on him) has narrated a Hadith on the authority of Ibn Asaker:
Translation: It has been narrated on the authority of Hadhrat Zaid bin Thabit (May Allah be well pleased with him), he said: I heard the Holy Prophet (Sallallahu alaihi wa sallam) say: Uthman passed by me. At that time, an angel was present before me. He said: Hadhrat ‘Uthman is a martyr. His own people will martyr him. All us angels are modest before ‘Uthman. (Tarikh Ul Khulafa, Vol. 1, Pg. No. 62)