Narrated Haritha bin Wahb (Radi-Allahu 'anhu):
I heard the Prophet (Sallallahu 'Alaihi Wa Sallam) saying, "Shall I tell
you of the people of Paradise? They comprise every poor humble person, and
if he swears by Allah to do something, Allah will fulfill it; while the
people of the fire comprise every violent, cruel and arrogant person."
Bukhari Vol. 8 : No. 651