Short answer
Backbiting (ghibah) is saying something true about a person in their absence that they would dislike. If it is untrue, it is slander (buhtan), which is worse. Backbiting is a major sin by the agreement of the scholars, and listening to it without objecting shares in the sin. A few real needs make it allowed, such as seeking advice or warning someone.
Ghibah is haram and a major sin, and so is willingly listening to it. It is permitted for a valid need: complaining of injustice to someone who can help, seeking a fatwa, warning others of harm, honest advice about a marriage or business partner, or identifying someone by a known description.
The four schools agree on this.
Explanation
The Quran compares backbiting to eating the flesh of your dead brother. The Prophet ﷺ defined it as mentioning your brother with what he dislikes. When asked what if it is true, he said: if it is true you have backbitten him, and if it is not true you have slandered him. So 'but it's true' is no defence.
Backbiting is not only words. It includes mimicking someone, a meaningful look, a screenshot shared in a group chat, a meme about a real person, or 'I'm not saying anything, but...'. Gossip that carries words between people to cause trouble is namimah, and the Prophet ﷺ said the talebearer will not enter Paradise.
The scholars list cases where speaking about someone is allowed:
- Complaining of injustice to someone who can help, such as a judge, a manager or a parent. The Quran allows the wronged person to speak.
- Seeking a fatwa: 'My husband does this; what should I do?'
- Honest advice when asked about a marriage proposal or business partner. The Prophet ﷺ himself told Fatimah bint Qays that one suitor was poor.
- Warning people of real harm, such as a fraudster.
- Speaking of a sin someone does openly and proudly, limited to that sin.
To repent: stop, regret it and resolve not to return. If the person has heard of it, ask their forgiveness. If telling them would only cause hurt, pray for them and praise them in the same places where you spoke ill. When others backbite in front of you, change the subject or defend your brother. The four schools agree on all of this.
The evidence
Quran, Surah Al-Hujuraat 49:12
يَٰٓأَيُّهَا ٱلَّذِينَ ءَامَنُوا۟ ٱجْتَنِبُوا۟ كَثِيرًۭا مِّنَ ٱلظَّنِّ إِنَّ بَعْضَ ٱلظَّنِّ إِثْمٌۭ ۖ وَلَا تَجَسَّسُوا۟ وَلَا يَغْتَب بَّعْضُكُم بَعْضًا ۚ أَيُحِبُّ أَحَدُكُمْ أَن يَأْكُلَ لَحْمَ أَخِيهِ مَيْتًۭا فَكَرِهْتُمُوهُ ۚ وَٱتَّقُوا۟ ٱللَّهَ ۚ إِنَّ ٱللَّهَ تَوَّابٌۭ رَّحِيمٌۭ ﴿١٢﴾
O you who have believed, avoid much [negative] assumption. Indeed, some assumption is sin. 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. And fear Allah; indeed, Allah is Accepting of repentance and Merciful.
Backbiting is forbidden and compared to eating a dead brother's flesh.
Quran, Surah An-Nisaa 4:148
۞ لَّا يُحِبُّ ٱللَّهُ ٱلْجَهْرَ بِٱلسُّوٓءِ مِنَ ٱلْقَوْلِ إِلَّا مَن ظُلِمَ ۚ وَكَانَ ٱللَّهُ سَمِيعًا عَلِيمًا ﴿١٤٨﴾
Allah does not like the public mention of evil except by one who has been wronged. And ever is Allah Hearing and Knowing.
The wronged person may speak about the wrong done to him.
Sahih Muslim 2589
Sahih... إن كان فيه ما تقول فقد اغتبته وإن لم يكن فيه فقد بهته ...
"If what you say is in him, you have backbitten him; if it is not in him, you have slandered him."
Backbiting is true speech that he would dislike; false speech is slander.
Sahih al-Bukhari 6056
Sahih... لا يدخل الجنة قتات ...
"The talebearer will not enter Paradise."
Carrying gossip between people is a major sin.
Sahih Muslim 1480
Sahih... أما معاوية فصعلوك لا مال له ...
"As for Mu'awiyah, he is poor and has no wealth."
Honest advice about a suitor is allowed.
Where the ruling is recorded
- al-Adhkar (Nawawi), Chapters on backbiting and talebearing. Defines ghibah, lists the six cases where it is allowed, and explains repentance.
- Ihya Ulum al-Din (al-Ghazali), Kitab Afat al-Lisan, section on backbiting. Explains the forms of backbiting and how to repent from it.
This answer is pending review by the scholars on our team. Quran translation by Sahih International. Hadith Arabic from the standard editions of the six books and the Muwatta, with gradings as recorded there; the English is our own rendering. Spotted a mistake? Tell us.