From the route of Abu Hurayrah, may Allah accept his deeds, who said: The Messenger of Allah, sallallahu ^alayhi wa sallam, said:
<< Do not envy one another, and do not cheat one another, and do not hate one another, and do not turn away from one another and do not under sell the concluded sales of one another. O Worshippers of Allah, be brethrens.
The Muslim is a brother to the Muslim and does not do him injustice, and does not turn him down, does not lie to him and does not look down upon him. Piety is right in here (pointing thrice to his chest). It is enough evil for one to look down upon his Muslim brother.
All that involves a Muslim whether his life, money or elements of integrity (reputation, wife, honor etc…) is unlawful to be violated by another Muslim.>>
Narrated by Muslim.