1. I don’t trust anyone who talks bad about someone else to me, they probably talk behind my back too.
2. People will question all the good things they hear about you but believe all the bad without a second thought.
3. "Do you know what is backbiting?"
They (the Companions) said: "Allah and His Messenger know best."Thereupon he (the Holy Prophet) said: Backbiting implies your talking about your brother in a manner which he does not like. It was said to him: "What is your opinion about this that if I actually find (that failing) in my brother which I made a mention of?" He said: "If (that failing) is actually found (in him) what you assert, you in fact backbited him, and if that is not in him it is a slander."
[Sahih Muslim 2589]