Musnad Ahmad 27:1588

Hashim narrated to us, Abd al-Rahman—meaning Ibn Abd Allah ibn Dinar—narrated to us, from Zayd ibn Aslam, from Abd Allah ibn Umar, from the Messenger of Allah (may Allah bless him and grant him peace), who said: "Whoever withdraws a hand from obedience, he has no argument on the Day of Resurrection. And whoever dies while separated from the community, he has died a death of ignorance."