Musnad Ahmad 27:1226

'Affan narrated to us, Khalid bin al-Harith narrated to us, Muhammad bin 'Ajlan narrated to us, from Zayd bin Aslam, from Ibn 'Umar, who said: I heard the Messenger of Allah (peace and blessings of Allah be upon him) saying: "Whoever withdraws his hand from obedience, there is no proof for him on the Day of Resurrection. And whoever dies while having separated from the community, he dies a death of ignorance (Jahiliyyah)."