Some people came to ʿAli ؓ and complained about ʿUthmanʿs tax collector. My father said to me: take this letter to ʿUthman ؓ and tell him: The people are complaining about your tax collector, and this is the instruction of the Messenger of Allah ﷺ about collecting zakah, tell them to follow it. So I went to ʿUthman and told him about that, He (the narrator) said: If he [ʿAli] had wanted to say anything about ʿUthman, he would have said it on that occasion - i.e., saying something bad.  

جَاءَ إِلَى عَلِيٍّ نَاسٌ مِنَ النَّاسِ فَشَكَوْا سُعَاةَ عُثْمَانَ قَالَ فَقَالَ لِي أَبِي اذْهَبْ بِهَذَا الْكِتَابِ إِلَى عُثْمَانَ فَقُلْ لَهُ إِنَّ النَّاسَ قَدْ شَكَوْا سُعَاتَكَ وَهَذَا أَمْرُ رَسُولِ اللهِ ﷺ فِي الصَّدَقَةِ فَمُرْهُمْ فَلْيَأْخُذُوا بِهِ قَالَ فَأَتَيْتُ عُثْمَانَ فَذَكَرْتُ ذَلِكَ لَهُ قَالَ فَلَوْ كَانَ ذَاكِرًا عُثْمَانَ بِشَيْءٍ لَذَكَرَهُ يَوْمَئِذٍ يَعْنِي بِسُوءٍ