Musnad Ahmad 89
It was narrated from Ma'dan bin Abi Talhah that 'Umar bin al Khattab delivered a khutbah on Friday, and he mentioned the Prophet of Allah ﷺ and Abu Bakr رضي الله عنه . He said:
I saw a dream that I can only interpret as meaning that my death is near; I saw as if a rooster pecked me twice, and I was told that it was a red rooster. I told this dream to Asma’ bint 'Umais, the wife of Abu Bakr , and she said: You will be killed by a Persian man. The people are asking me to appoint a successor, but Allah will not cause His religion and His caliphate, with which He sent His Prophet ﷺ to be lost. If death comes to me soon, then the caliphate is to be decided by these six men with whom the Messenger of Allah (ﷺ) was pleased when he died. Whichever of them you swear allegiance to, then listen to him and obey. I know that some people will object to this matter. I have fought them with my own hands in the defence of Islam. 
They are the enemies of Allah and misguided kafirs. By Allah, I am not leaving behind anything that my Lord instructed me to do and I came to the position of caliphate on that basis that is more important to me than kalalah. By Allah, the Prophet of Allah ﷺ never emphasised any issue to me since I accompanied him more than the issue of kalalah, until he poked me in the chest with his finger and said: `Is not ayatas-saif (the verse of summer, i.e., it was revealed in summer), which appears at the end of Sooratan Nisa', sufficient for you?` If I live I will issue a decree that will be so clear that those who read the Qur'an and those who do not read it will be able to make decisions concerning it. I call upon Allah to bear witness over the governors of the regions, for I only sent them to be just and to teach the people their religion and the Sunnah of the Prophet ﷺ and to refer to me concerning any difficult matter. O people, you eat two plants which I find to be nothing but repugnant, this onion and garlic. I remember the Messenger of Allah ﷺ, if he noticed their smell coming from a man in the mosque, he would issue orders that he taken out from the mosque to al-Baqee'. Whoever must eat them, let him cook them to death.” 

He said: He addressed the people on Friday and was attacked on Wednesday.
حَدَّثَنَا عَفَّانُ، حَدَّثَنَا هَمَّامُ بْنُ يَحْيَى، قَالَ حَدَّثَنَا قَتَادَةُ، عَنْ سَالِمِ بْنِ أَبِي الْجَعْدِ الْغَطَفَانِيِّ، عَنْ مَعْدَانَ بْنِ أَبِي طَلْحَةَ الْيَعْمَرِيِّ، أَنَّ عُمَرَ بْنَ الْخَطَّابِ، رَضِيَ اللَّهُ عَنْهُ قَامَ عَلَى الْمِنْبَرِ يَوْمَ الْجُمُعَةِ فَحَمِدَ اللَّهَ وَأَثْنَى عَلَيْهِ ثُمَّ ذَكَرَ رَسُولَ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ وَذَكَرَ أَبَا بَكْرٍ رَضِيَ اللَّهُ عَنْهُ ثُمَّ قَالَ رَأَيْتُ رُؤْيَا لَا أُرَاهَا إِلَّا لِحُضُورِ أَجَلِي رَأَيْتُ كَأَنَّ دِيكًا نَقَرَنِي نَقْرَتَيْنِ قَالَ وَذَكَرَ لِي أَنَّهُ دِيكٌ أَحْمَرُ فَقَصَصْتُهَا عَلَى أَسْمَاءَ بِنْتِ عُمَيْسٍ امْرَأَةِ أَبِي بَكْرٍ رَضِيَ اللَّهُ عَنْهُمَا فَقَالَتْ يَقْتُلُكَ رَجُلٌ مِنْ الْعَجَمِ قَالَ وَإِنَّ النَّاسَ يَأْمُرُونَنِي أَنْ أَسْتَخْلِفَ وَإِنَّ اللَّهَ لَمْ يَكُنْ لِيُضَيِّعَ دِينَهُ وَخِلَافَتَهُ الَّتِي بَعَثَ بِهَا نَبِيَّهُ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ وَإِنْ يَعْجَلْ بِي أَمْرٌ فَإِنَّ الشُّورَى فِي هَؤُلَاءِ السِّتَّةِ الَّذِينَ مَاتَ نَبِيُّ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ وَهُوَ عَنْهُمْ رَاضٍ فَمَنْ بَايَعْتُمْ مِنْهُمْ فَاسْمَعُوا لَهُ وَأَطِيعُوا وَإِنِّي أَعْلَمُ أَنَّ أُنَاسًا سَيَطْعَنُونَ فِي هَذَا الْأَمْرِ أَنَا قَاتَلْتُهُمْ بِيَدِي هَذِهِ عَلَى الْإِسْلَامِ أُولَئِكَ أَعْدَاءُ اللَّهِ الْكُفَّارُ الضُّلَّالُ وَايْمُ اللَّهِ مَا أَتْرُكُ فِيمَا عَهِدَ إِلَيَّ رَبِّي فَاسْتَخْلَفَنِي شَيْئًا أَهَمَّ إِلَيَّ مِنْ الْكَلَالَةِ وَايْمُ اللَّهِ مَا أَغْلَظَ لِي نَبِيُّ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ فِي شَيْءٍ مُنْذُ صَحِبْتُهُ أَشَدَّ مَا أَغْلَظَ لِي فِي شَأْنِ الْكَلَالَةِ حَتَّى طَعَنَ بِإِصْبَعِهِ فِي صَدْرِي وَقَالَ تَكْفِيكَ آيَةُ الصَّيْفِ الَّتِي نَزَلَتْ فِي آخِرِ سُورَةِ النِّسَاءِ وَإِنِّي إِنْ أَعِشْ فَسَأَقْضِي فِيهَا بِقَضَاءٍ يَعْلَمُهُ مَنْ يَقْرَأُ وَمَنْ لَا يَقْرَأُ وَإِنِّي أُشْهِدُ اللَّهَ عَلَى أُمَرَاءِ الْأَمْصَارِ إِنِّي إِنَّمَا بَعَثْتُهُمْ لِيُعَلِّمُوا النَّاسَ دِينَهُمْ وَيُبَيِّنُوا لَهُمْ سُنَّةَ نَبِيِّهِمْ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ وَيَرْفَعُوا إِلَيَّ مَا عُمِّيَ عَلَيْهِمْ ثُمَّ إِنَّكُمْ أَيُّهَا النَّاسُ تَأْكُلُونَ مِنْ شَجَرَتَيْنِ لَا أُرَاهُمَا إِلَّا خَبِيثَتَيْنِ هَذَا الثُّومُ وَالْبَصَلُ وَايْمُ اللَّهِ لَقَدْ كُنْتُ أَرَى نَبِيَّ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ يَجِدُ رِيحَهُمَا مِنْ الرَّجُلِ فَيَأْمُرُ بِهِ فَيُؤْخَذُ بِيَدِهِ فَيُخْرَجُ بِهِ مِنْ الْمَسْجِدِ حَتَّى يُؤْتَى بِهِ الْبَقِيعَ فَمَنْ أَكَلَهُمَا لَا بُدَّ فَلْيُمِتْهُمَا طَبْخًا قَالَ فَخَطَبَ النَّاسَ يَوْمَ الْجُمُعَةِ وَأُصِيبَ يَوْمَ الْأَرْبِعَاءِ‏.‏