Abu Dawud Book 35, Hadith Number 4617.

Narated By AbuBakrah : One day the Prophet (PBUH) said: Which of you had dream? A man said: It is I. I saw as though a scale descended from the sky. You and AbuBakr were weighed and you were heavier; AbuBakr and Umar were weighed and AbuBakr was heavier: Umar and Uthman were weighed and Umar was heavier; than the scale was taken up. we saw signs of dislike on the face of the Apostle of Allah (PBUH).