Musnad Ahmad 1207
It was narrated that Qais bin `Ubad said:
We were with `Ali (رضي الله عنه) and when he saw any event or reached the top of a hill or went down in a valley, he said: Glory be to Allah; Allah and His Messenger spoke the truth. I said to a man of Banu Yashkur: Let us go to Ameer al-Mu`mineen and ask him why he says, Allah and His Messenger spoke the truth. So we went to him and we said: O Ameer al-Mu`mineen, when you see any event or reach the top of a hill or go down into a valley, you say: Allah and His Messenger spoke the truth. Did the Messenger of Allah (ﷺ) instruct you exclusively to say that? He turned away from us but we persisted in asking. When he realised that, he said: By Allah, the Messenger of Allah (ﷺ) did not tell me anything exclusively that he did not tell to other people, but the people attacked ‘Uthman bin `Affan (رضي الله عنه) and killed him, and there were people who were worse than me in action and attitude concerning him. Then I thought that I was most deserving of this position, so I accepted it. And Allah knows best whether we are right or wrong.
حَدَّثَنَا عَبْدُ الرَّزَّاقِ، أَنْبَأَنَا مَعْمَرٌ، عَنْ عَلِيِّ بْنِ زَيْدٍ، عَنِ الْحَسَنِ، عَنْ قَيْسِ بْنِ عُبَادٍ، قَالَ كُنَّا مَعَ عَلِيٍّ رَضِيَ اللَّهُ عَنْهُ فَكَانَ إِذَا شَهِدَ مَشْهَدًا أَوْ أَشْرَفَ عَلَى أَكَمَةٍ أَوْ هَبَطَ وَادِيًا قَالَ سُبْحَانَ اللَّهِ صَدَقَ اللَّهُ وَرَسُولُهُ فَقُلْتُ لِرَجُلٍ مِنْ بَنِي يَشْكُرَ انْطَلِقْ بِنَا إِلَى أَمِيرِ الْمُؤْمِنِينَ حَتَّى نَسْأَلَهُ عَنْ قَوْلِهِ صَدَقَ اللَّهُ وَرَسُولُهُ قَالَ فَانْطَلَقْنَا إِلَيْهِ فَقُلْنَا يَا أَمِيرَ الْمُؤْمِنِينَ رَأَيْنَاكَ إِذَا شَهِدْتَ مَشْهَدًا أَوْ هَبَطْتَ وَادِيًا أَوْ أَشْرَفْتَ عَلَى أَكَمَةٍ قُلْتَ صَدَقَ اللَّهُ وَرَسُولُهُ فَهَلْ عَهِدَ رَسُولُ اللَّهِ إِلَيْكَ شَيْئًا فِي ذَلِكَ قَالَ فَأَعْرَضَ عَنَّا وَأَلْحَحْنَا عَلَيْهِ فَلَمَّا رَأَى ذَلِكَ قَالَ وَاللَّهِ مَا عَهِدَ إِلَيَّ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ عَهْدًا إِلَّا شَيْئًا عَهِدَهُ إِلَى النَّاسِ وَلَكِنَّ النَّاسَ وَقَعُوا عَلَى عُثْمَانَ رَضِيَ اللَّهُ عَنْهُ فَقَتَلُوهُ فَكَانَ غَيْرِي فِيهِ أَسْوَأَ حَالًا وَفِعْلًا مِنِّي ثُمَّ إِنِّي رَأَيْتُ أَنِّي أَحَقُّهُمْ بِهَذَا الْأَمْرِ فَوَثَبْتُ عَلَيْهِ فَاللَّهُ أَعْلَمُ أَصَبْنَا أَمْ أَخْطَأْنَا‏.‏