Back-biting. A statement made about someone in their absence that would displease that person if they were aware of it – a statement which is true about them.
Qurʾān sūrah (chapter) 49, ayah (line) 12 famously compares the action of ghībah to consuming the flesh of one’s dead brother. Sahih International translates:
“... And do not spy or backbite each other. Would one of you like to eat the flesh of his brother when dead? You would detest it. ...(49:12)”
Ghībah is a very serious sin in Islam. It is haram (forbidden) both to commit back-biting and to listen to it. Ghībah is a sin that violates both Allah’s rights (Truth. Alternate translations, ‘reality’ or ‘right/correct’. Haqq is the opposite of bāṭil, which means false/falsehood. ‘Al-Haqq’ is one of the names and attributes of Allah. This can be simultaneously understood to mean that Allah embodies... More The proper name of God in Islam and in Arabic, referring to all of His perfect attributes at once. This name is a proper noun, and no other entity or being is allowed to have... More) and man’s rights (The rights of man, defined by a person’s obligations to others. All rights belong to Allah (Haqq Allah), but some are in a subset (Haqq al-Nas) that belongs to both people and Allah. Sins that... More). Therefore, the sinner must secure the back-bitten person’s forgiveness, as well as make tawbah (repent to God), in order to expunge the sin.