Sayyidah Umm al-Ala' (may Allah be pleased with her) said: Uthman bin Maz'un (may Allah be pleased with him) passed away, then the Prophet (peace and blessings be upon him) came to him, and I said: May Allah have mercy on you, O Abu al-Sa'ib! I bear witness about you that Allah has surely honoured you. The Prophet (peace and blessings be upon him) said: "How do you know that Allah has honoured him?" I said: I do not know. He (peace and blessings be upon him) said: "As for him, the certainty (death) has come to him from his Lord. By Allah, I am the Messenger of Allah, and I do not know what will be done with me, nor with you." I said: By Allah, I will never again bear witness about anyone. The narrator said: Then I saw in a dream a spring flowing for Uthman, so I asked the Prophet (peace and blessings be upon him), and he (peace and blessings be upon him) said: "That is his deeds."
Hadith Referenceالمعجم الكبير للطبراني / مسند النساء / 21799