It was narrated from Abu Hurayrah (may Allaah be pleased with him)
that the Messenger of Allaah (peace and blessings of Allaah be upon him) said:
“Do you know what gheebah (backbiting) is?”
They (the companions) said, “Allaah and His Messenger know best.”
He (peace be upon him) said,
“It is saying something about your brother which he whould dislike.”
Someone asked 'What if I say something about my brother which is true?'
The Prophet (peace be upon him) replied,
'If what you say of him is true, it is backbiting
and if it is not true you have slandered him.'
{ Sahih Muslim }
