Abu Dawud Book 14, Hadith Number 3227.
Chapter : Not known.
Narated By AbuHurayrah : People with a bier passed by the Apostle of Allah (PBUH). They (the companions) spoke highly of him. He said: Paradise is certain for him. Then some people with another (bier) passed by him. They spoke very badly of him. He said: Hell is certain for him. He then said: Some of you are witness to others.