Musnad Ahmad 27:1685

Ya'qub narrated to us, my father narrated to us, from Salih, Nafi' narrated to me, that Abdullah ibn Umar informed him, saying: The Messenger of Allah, peace and blessings of Allah be upon him, looked upon the people of the pit at Badr, then he called out to them, saying: "O people of the pit, have you found what your Lord promised you to be true?" Some of his companions said: "O Messenger of Allah, are you calling out to dead people?" The Messenger of Allah, peace and blessings of Allah be upon him, said: "You are not more hearing to what I said than they are."