Musnad Ahmad 2:8

'Affan narrated to us, Hammam ibn Yahya narrated to us, he said: Qatadah narrated to us, from Salim ibn Abi al-Ja'd al-Ghatafani, from Ma'dan ibn Abi Talhah al-Ya'mari: That 'Umar ibn al-Khattab stood upon the pulpit on Friday. He praised Allah and extolled Him, then he mentioned the Messenger of Allah, peace and blessings of Allah be upon him, and he mentioned Abu Bakr. Then he said: "I have seen a vision, and I do not see it as anything but the approach of my term. I saw as if a rooster pecked me twice." He said: "And it was mentioned to me that it was a red rooster." "I related it to Asma bint 'Umays, the wife of Abu Bakr, may Allah be pleased with them both, and she said: 'A man from the non-Arabs (Ajam) will kill you.'" "And the people are commanding me to appoint a successor, but Allah would not let His religion go to waste, nor His Caliphate with which He sent His Prophet, peace and blessings of Allah be upon him. If the matter hastens for me, then the Shura (consultation) is among these six whom the Prophet of Allah, peace and blessings of Allah be upon him, died while he was pleased with them. So whomever you pledge allegiance to among them, then listen to him and obey him. And I know that people will criticize this matter; I fought them with this hand of mine for the sake of Islam, and those are the enemies of Allah, the disbelievers, the misguided." "By Allah, I do not leave behind anything regarding what my Lord entrusted to me and appointed me as a successor for that is more important to me than the *Kalalah* (one who leaves behind neither ascendants nor descendants). By Allah, the Prophet of Allah, peace and blessings of Allah be upon him, was never as harsh with me regarding anything since I accompanied him as he was harsh with me regarding the matter of the *Kalalah*, until he poked his finger into my chest and said: 'The verse of the summer, which was revealed at the end of Surat an-Nisa', is sufficient for you.' And if I live, I will issue a judgment regarding it that will be known by those who read and those who do not read." "And I call Allah to witness over the governors of the provinces, that I only sent them to teach the people their religion, to clarify to them the Sunnah of their Prophet, peace and blessings of Allah be upon him, and to refer to me whatever is obscure to them." "Then, O people, you eat from two trees which I do not see as anything but foul: this garlic and onion. By Allah, I used to see the Prophet of Allah, peace and blessings of Allah be upon him, find their odor on a man, so he would order him to be taken by the hand and led out of the mosque until he was brought to al-Baqi'. So whoever eats them, he must kill their odor by cooking." He said: So he addressed the people on Friday, and he was struck on Wednesday.