Musnad Ahmad 2:105

Yahya ibn Sa'id narrated to us, I asked him, Hisham narrated to us, Qatadah narrated to us, from Salim ibn Abi al-Ja'd, from Ma'dan ibn Abi Talhah: That Umar delivered a sermon on a Friday, and he mentioned the Prophet of Allah, may Allah bless him and grant him peace, and he mentioned Abu Bakr, may Allah be pleased with him, and said: "I have seen as if a rooster pecked me twice, and I do not see it as anything but the approach of my death. And there are people who command me to appoint a successor, but Allah would not let His religion or His caliphate be lost, nor that which He sent His Prophet, may Allah bless him and grant him peace, with. If a matter hastens me, then the caliphate is a matter of consultation among these six whom the Messenger of Allah, may Allah bless him and grant him peace, died while he was pleased with them. And I know that some people will criticize this matter—I struck them with this hand of mine for the sake of Islam—so if they do that, then those are the enemies of Allah, the disbelievers, the misguided." "And I do not leave behind me anything more important to me than the *kalalah* (inheritance of one who leaves no direct descendants or ascendants). The Messenger of Allah, may Allah bless him and grant him peace, was never as harsh with me regarding anything since I accompanied him as he was harsh with me regarding the *kalalah*, and I never argued with him about anything as I argued with him about the *kalalah*, until he poked his finger into my chest and said: 'O Umar, does the summer verse which is at the end of Surat an-Nisa' not suffice you?' If I live, I will issue a judgment regarding it that will be judged by those who recite the Quran and those who do not recite the Quran." Then he said: "O Allah, I call You to witness over the governors of the provinces, for I only sent them to teach the people their religion and the Sunnah of their Prophet, may Allah bless him and grant him peace, and to distribute their spoils among them, and to be just with them, and to refer to me whatever becomes difficult for them regarding their affairs." "O people, you eat from two trees which I do not see as anything but foul. I have seen the Messenger of Allah, may Allah bless him and grant him peace, when he would detect their odor from a man in the mosque, he would order him to be taken by the hand and led out to al-Baqi'. So whoever eats them, let him kill them by cooking."