In ancient Greece , Socrates was reputed to hold knowledge in high esteem. One day an acquaintance met the great philosopher and said, “Do you know what I just heard about your friend?”
“Hold on a minute,” Socrates replied. “Before you talk to me about my friend it might be a good idea to take a moment and filter what you are going to say. Let’s do a Triple Filter Test. The first filter is Truth. Are you absolutely sure that what you are about to tell me is true?”
“No,” the man said, “actually I just heard about it…”
“All right,” said Socrates. “So you don’t really know if it’s true or not. Now let’s try the second filter, the filter of Goodness. Is what you are about to tell me about my friend something good?”
“No, on the contrary…”, said the acquaintance.
“So,” Socrates continued, “you want to tell me something bad about my friend, but you’re not certain if it’s true. You may still pass the test though, because there’s one filter left: the filter of Usefulness. Is what you want to tell me about my friend going to be useful to me?”
“No, not really.”, replied the acquaintance.
Socrates replied, “Well, if what you want to tell me is neither true nor good nor even useful, why tell it to me at all?”
In the Quran, it says:
O you who have believed, let not a people ridicule [another] people; perhaps they may be better than them; nor let women ridicule [other] women; perhaps they may be better than them. And do not insult one another and do not call each other by [offensive] nicknames. Wretched is the name of disobedience after [one’s] faith. And whoever does not repent – then it is those who are the wrongdoers. (Surat Al-Ĥujurāt 49:11)
Abu Huraira reported Allah’s Messenger (PBUH) as asking: “Do you know what is backbiting?”
They (the Companions) said: “Allah and His Messenger (PBUH)know best.
Thereupon the Holy Prophet (PBUH) 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?
Prophet (PBUH) replied: “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.”
Reference: Sahih Muslim Book 32 Hadith 6265