She informed him that the Muhajirun drew lots, and Uthman bin Mazun fell to our share, so we lodged him in our homes. He fell ill with the sickness from which he died. When he passed away and was washed and shrouded in his garments, the Messenger of Allah ﷺ entered.I said, "May Allah's mercy be upon you, Abu Saaib. My testimony for you is that Allah has honored you."The Prophet ﷺ said, "How do you know that Allah has honored him?"I replied, "May my father be your ransom, Messenger of Allah, who else would Allah honor?"He said, "As for him, certainty has come to him, and by Allah, I hope good for him. By Allah, even though I am the Messenger of Allah ﷺ, I do not know what will be done with me."She said, "By Allah, I will never declare anyone pure after him."
أخبرته أنه اقتسم المهاجرون قرعة، فطار لنا عثمان بن مظعون، فأنزلناه في أبياتنا، فوجع وجعه الذي توفي فيه، فلما توفي وغسل وكفن في أثوابه دخل رسول الله ﷺ فقلت: رحمة الله عليك أبا السائب، فشهادتي عليك، لقد أكرمك الله. فقال النبي ﷺ: وما يدريك أن الله أكرمه؟ فقلت: بأبي أنت يا رسول الله، فمن يكرمه الله؟ فقال: أما هو فقد جاءه اليقين، والله إني لأرجو له الخير، والله ما أدري وأنا رسول الله ﷺ ما يفعل بي. قالت: فوالله لا أزكي أحدا بعده أبدا.
Bukhari narrated it in the Book of Funerals (1243) from Yahya bin Bukayr, who said, Layth narrated to us, from Aqeel, from Ibn Shihab, who said, Kharija bin Zayd bin Thabit informed me that Umm Ala said, and then he mentioned it. Uthman bin Mazun died after witnessing Badr, in the second year of the Hijrah, and he was the first of the Emigrants to die in Madinah, and the first to be buried in Baqi.As for his statement, "By Allah, I do not know, though I am the Messenger of Allah ﷺ, what will be done with me," Ibn Hajar said in Fath al-Bari (3/115-116), "The Messenger of Allah ﷺ said that in agreement with the words of Allah, the Exalted, in Surah Ahqaf, "Say, I am not something new among the messengers, and I do not know what will be done with me or with you" [Ahqaf 46:9], and that was before the revelation of His saying, the Exalted, "That Allah may forgive you your past and future sins" [Fath 48:2], since Ahqaf is Meccan and Surah Fath is Medinan without any disagreement about either. It has been established that he ﷺ said, 'I am the first to enter Paradise,' along with other reports that are explicit in this meaning." End of quote.I say, perhaps he said that out of humility toward Allah, the Exalted, and there are other opinions on this. Refer to Nawasikh al-Quran by Ibn Jawzi and others.