Sahih Muslim Book 042, Hadith Number 7067.
Chapter : Not known.
'Abdullah b. 'Amr b. al-As reported that Allah's Messenger (may peace be upon him) said: How would you be, O people, when Persia and Rome would be conquered for you? 'Abd at-Rahman b Auf said: We would say as Allah has commanded us and we would express our gratitude to Allah Thereupon Allah's Messenger (may peace be upon him) said: Nothing else besides it? You would (in fact) vie with one another, then you would feel jealous, then your relations would be estranged and then you will bear enmity against one another or something to the same effect. Then you would go to the poor emigrants and would make some the masters of the others.