Envy and Fighting for Worldly Fortunes

Narrated by 'Uqba bin 'Amr (Radhi Allahu Anhu): The Prophet (Sallallahu 'Alayhi wa Sallam) once came out and offered the funeral prayer for the martyrs of Uhud, and proceeded to the pulpit and said, "I shall be your predecessor and a witness on you, and I am really looking at my sacred Fount now, and no doubt, I have been given the keys of the treasures of the world. By Allah, I am not afraid that you will worship others along with Allah, but I am afraid that you will envy and fight one another for worldly fortunes." (Al-Bukhari)